PROCESS FOR PREPARING 5,8-DIHYDRONAPHTHOQUINONE DERIVATIVES, NOVEL 5,8-DIHYDRONAPHTHOQUINONE DERIVATIVES AND THEIR USE AS ANTICANCER AGENT

Abstract: The present invention relates to a process for preparing 5,8-dihydronaphthoquinone derivatives represented by general formula (I) in which R<1> represents alkyl or alkenyl, R<2> represents hydrogen, alkyl or a group -C(O)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen atom(s), and R<3> represents hydrogen or alkyl, characterized in that: (A) a compound having general formula (II) in which R<1>, R<2> and R<3> are defined as previously described and R<4> represents alkyl, is oxidized with cerium(IV) ammonium nitrate in a suitable solvent, or (B) a compound having general formula (Ia) in which R<1> and R<2> are defined as previously described and R<3a> represents alkyl, is dealkylated to prepare a compound having general formula (Ib) in which R<1> and R<2> are defined as previously described, or (C) a compound having general formula (Ic) in which R<1> and R<3> are defined as previously described, is reacted with a compound of formula RCOOH wherein R is defined as previously described, in the presence of an organic base and dicyclohexylcarbodiimide to prepare a compound having general formula (Id) in which R<1>, R<3> and R are defined as previously described. In addition, the present invention relates to a novel 5,8-dihydronaphthoquinone derivative of formula (I) wherein when R<2a> is hydrogen or a group -C(O)R and R<3> is hydrogen, R<1> is other than 3-methyl-2-butenyl; and when R<2a> and R<3> independently of one another represent hydrogen or methyl, R<1> is other than 3-methylbutyl, and its use as an anticancer agent.

Description: PROCESS FOR PREPARING 5 , 8-DIHYDRONAPHTHOQUINONE DERIVA¬ TIVES, NOVEL 5, 8-DIHYDRONAPHTHOQUINONE DERIVATIVES AND THEIR USE AS ANTICANCER AGENT TECHNICAL FIELD The present invention relates to a process for prepar¬ ing 5, 8-dihydronaphthoquinone derivatives represented by the following general formula (I) which has an excellent anticancer activity : in which R 1 represents alkyl or alkenyl, R 2 represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen(s) , and R- represents hydrogen or alkyl. The present invention also relates to a 5,8-dihydro- naphthoquinone derivative represented by the following general formula (IA) , which is considered as the novel compound among the compounds of formula (I) above : in which represents alkyl or alkenyl, R 2a represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen(s) , and R represents hydrogen or alkyl, provided that when R 2a is hydrogen or a group -C(0)R and R is hydrogen, R 1 is other than 3-methyl-2-butenyl; and when R 2a and R 3 independently of one another represent hydrogen or methyl, R is other than 3-methylbutyl. In addition, the present invention relates to use of the novel 5, 8-dihydronaphthoquinone derivative of formula (IA) as an anticancer agent. BACKGROUND ART Study of the method for treatment of cancer as one of incurable diseases of today has been actively conducted by means of chemotherapy, physical therapy and genetic engi¬ neering technique, together with study of the mechanism of attack and progress of cancer. As one of various thera- peutic methods for treating cancer as mentioned above, chemotherapy attempts to treat cancer using anticancer agent. However, none of currently used anticancer agents has a satisfactory potent anticancer activity. According¬ ly, attempts have been continuously made to develope an anticancer agent having a new mechanism of action and a potent anticancer activity. Such attempt to develope an anticancer agent has extended to search for substances having anticancer activity in the field of organic chemical synthesis and natural substances and further to synthesize a pharmacologically active substance from derivatives produced by transforming the component isolated from the natural product with organic chemical techniques. As one of the progress of a series of such study, εhikonin having the following formula (A) and its deriva¬ tives were proposed: Shikonin [=2- (l-hydroxy-4-methyl-3-pentenyl) -5, 8- dihydroxy-1, 4-naphthoquinone] Shikonin was first isolated from Alkana tinctoria by H. Brockmann in 1936 [Ann. Chem. 521, 1-47(1936)] and then from various plants belonging to Borraginaceae, and has been known as a compound having anticancer activity. However, since shikonin itself has a week anticancer activ¬ ity and is difficult to absorb in the body, some deriva¬ tives wherein various substituents are introduced into a secondary alcoholic hydroxy group on 1' -position have been isolated from plants and then clinically used. Among them, typical known compounds are 1 '-O-acetylshikonin [2-(l -acetoxy-4-methyl-3-pentenyl) -5, 8-dihydroxy-l, 4-naphthoqui- none] , 1 ' -O-isobutanoylshikonin [2- (l-isobutanoyloxy-4- methyl-3-pentenyl) -5, 8-dihydroxy-l, 4-naphthoquinone] and 1 '-0-(3,3-dimethyl) acrylshikonin [2-(l-(3, 3-dimethyl) acryl- oxy-4-methyl-3-pentenyl) -5, 8-dihydroxy-l, 4-naphthoquinone] . Thereafter, extensive study to develope shikonin derivatives has been continuously made. As a result, numerous compounds having various acyl groups introduced into the alcoholic hydroxy group of shikonin have been developed. However, for preparation of such acyl deriva- tives of shikonin, a method for selectively acylating only the secondary alcoholic hydroxy group among three hydroxy groups, i.e. two phenolic hydroxy groups and one alcoholic hydroxy group, present in shikonin (A) is required. Conventional methods which have been generally used for this purpose include, for example, a method for protecting the phe-nolic hydroxy group with a specific method, react¬ ing the alcoholic hydroxy group of shikonin with acid halide and then removing the protecting group [see, German Laid-open Patent Publication No. 2831786] ; a method for reacting shikonin (A) with acid halide in the presence of zeolite [see, Japanese Laid-open Patent Publication No. (sho) 61-151151] ; and the like. However, such known methods have disadvantages in that they consist of multi- step procedures and therefore are complicated, and they are lacking in selectivity to produce a lot of by-product, and therefore the yield of the desired acylshikonin derivatives is considerably low. Thus, the present inventors have extensively studied to find the method which can prepare acylshikonin deriva¬ tives in high yield. As a result, we have identified that this purpose can be established by the method according to the present invention as described hereinafter. In addi¬ tion, we have supposed that other shikonin derivatives, in addition to shikonin derivatives which can be separated directly from natural product, may also have more potential anticancer activity and then prepared numerous novel deriv- atives (IA) having a good activity, which cannot be sepa¬ rated from natural products, by introducing various sub¬ stituents into the side chain on 2-position of naphthoqui¬ none nucleus. Thus, now we have completed the present invention. DISCLOSURE OF INVENTION Accordingly, it is an object of the present invention to provide a novel process for preparing 5 , 8-dihydronaph- thoquinone derivatives having the following general formula (I) in which R represents alkyl or alkenyl, p R represents hydrogen, alkyl or a group -C (0) R wherein R represents alkyl , alkenyl , aryl , aralkyl or aralkenyl , which can be substituted or unsubstituted with one or more halogen atom (s) , and R- represents hydrogen or alkyl, characterized in that (A) a compound having the following general formula (II) m which R 1 , R2 and R 3 are defined as previously described and R represents alky, is oxidized with cerium(IV) ammonium nitrate in a suitable solvent, or (B) a compound having the following general formula (la) in which R 1 and R2 are defined as previously described and R 3a represents alkyl, is dealkylated to prepare a compound having the following general formula (lb) : in which R 1 and R2 ώ are defined as previously de¬ scribed, or (C) a compound having the following general formula (Ic) : in which R and R are defined as previously de¬ scribed, is reacted with a compound of formula RCOOH wherein R is defined as previously described, in the presence of an' organic base and dicyclohexylcarbodii- ide to prepare a compound having the following gener¬ al formula (Id) : in which R 1 , R 3 and R are defined as previously de¬ scribed. It is another object of the present invention to provide a novel 5, 8-dihydronaphthoquinone derivative repre- sented by the following general formula (IA) : in which R represents alkyl or alkenyl, R represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen(s), and R represents hydrogen or alkyl, provided that when R 2a is hydrogen or a group -C(0)R and R is hydrogen, R 1 is other than 3-methyl-2-butenyl; and when R and R independently of one another represent hydrogen or methyl, R 1 is other than 3-methylbutyl. It is a further object of the present invention to provide an anticancer agent containing a novel 5,8- dihydronaphthoquinone derivative of formula (IA) as defined above . BEST MODE FOR CARRYING OUT THE INVENTION In one aspect, the present invention relates to a novel process for preparing 5, 8-dihydronaphthoquinone derivatives having the general formula (I) as defined above. The process for preparing 5 , 8 -dihydronaphthoquinone derivatives according to the present invention can be represented by the following methods A to C : Method A ( ID Method B (la) (lb) Method C (Ic) (Id) In the above reaction scheme, R represents alkyl or alkenyl, p R represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen (s) , R represents hydrogen or alkyl, R 3a represents alkyl, and R 4 represents alkyl. In the specification of the present invention, the term "halogen" means fluoro, chloro, bromo, iodo, etc.; the term "alkyl" means a straight or branched, saturated hydro¬ carbon radical, preferably a radical having 1 to 20 carbon atoms, particularly having 1 to 12 carbon atoms; the term "alkenyl" means a straight or branched hydrocarbon radical containing one or more double bond(s) , preferably a radical having 2 to 20 carbon atoms, particularly having 2 to 12 carbon atoms; and the term "aryl" in "aryl", "aralkyl" and "aralkenyl" preferably means a unsaturated 6-membered ring. Hereinafter, the above Methods A to C according to the present invention will be more specifically explained. Method A According to the method A, the compound of formula (I) can be prepared by oxidizing a compound of formula (II) with cerium(IV) ammonium nitrate (CAN) in a suitable sol¬ vent. The solvent which can be used in this reaction is preferably an aprotic polar solvent such as acetonitrile, dimethylformamide, etc. In the preferred embodiment of the method A according to the present invention, first the compound of formula (II) is dissolved in the solvent and then the resulting solution is cooled, preferably to 0 to 5°C. An aqueous solution of CAN in 1 to 10 times molar amount, preferably 2 to 5 times molar amount, with respect to the compound of formula (II) is added thereto over preferably 10 minutes to 5 hours, particularly 20 minutes to one hour and the reac¬ tion solution is warmed to normal temperature and then allowed to react with stirring for several hours. When the reaction is completed, distilled water is added to the reaction mixture and the resulting product is extracted with a suitable solvent such as dichloro ethane, etc. , and then separated and purified by a conventional working-up procedure such as recrystallization or column chromatogra¬ phy. As an example of the compound of formula (I) which can be prepared by the method A according to the present inven¬ tion, the following compounds can be mentioned : 2- (1-hydroxypentyl) -5, 8-dimethoxy-1,4-naphthoquinone, 2-(1-hydroxyhexyl) -5, 8-dimethoxy-l,4-naphthoquinone, 2-(l-hydroxyoctyl) -5, 8-dimethoxy-l, 4-naphthoquinone, 2- (1-hydroxytridecyl) -5, 8-dimethoxy-l, 4-naphthoquinone, 2- (l-hydroxy-3-methyl-2-butenyl) -5, 8-dimethoxy-l, 4-naph- thoquinone , 2- ( l-acetoxy-4-methylpentyl ) -5 , 8-dimethoxy-l , 4-naphthoq- uinone , 2-(l-ethoxy-4-methylpentyl) -5,8-dimethoxy-l, 4-naphthoqu- inone, 2-[l- (3-methylbutoxy) -4-methylpentyl]-5, 8-dimethoxy-l,4- naphthoquinone, 2- (l-pentyloxy-4-methylpentyl) -5, 8-dimethoxy-l, 4-naphth- oquinone, 2- (l-heptyloxy-4-methylpentyl) -5, 8-dimethoxy-l, 4-naphth- oquinone, and 2-(l-dodecyloxy-4-methylpentyl) -5, 8-dimethoxy-l, 4-naph- thoquinone. Some of the compound of formula (II) used as a start¬ ing material in the method A above are known compounds but the other is a novel compound, which can be prepared by a method analogous to the known method for preparing the known compound of formula (II) . For example, the compound of formula (II) can be prepared (a) by reacting a compound having the following general formula (III) with magnesium halide of formula R 1 MgX to obtain the compound of formula (II) wherein R 2 is hydrogen, i.e. a compound of formula (Ila) , or (b) by alkylating the resulting compound of formula (Ila) to obtain the compound of formula (II) wherein R is alkyl, i.e. a compound of formula (lib) , or (c) by acylating the compound of formula (Ila) with a compound of formula RCOOH p to obtain the compound of formula (II) wherein R is -C(0)R, i.e. a compound of formula (lie). The process for preparing the compound of formula (II) of the present invention can be represented by the following reaction scheme : (lib) (He) In the above reaction scheme, R R 11 ,, R R 3 - , R R 44 aanndd RR aarree cdefined as previously described, and B represents alkyl According to the reaction (a) above, 2-formylnaphtha- lene derivative of formula (III) is dissolved in an ether solvent such as dimethylether, tetrahydrofuran, etc., and then reacted by adding magnesium halide of formula R^-MgX preferably in 1 to 10 times molar amount, particularly in 2 to 5 times molar amount, with respect to the o pound of formula (III) . Then, the reaction mixture is treated by conventional working-up procedure. For example, saturated aqueous ammonium chloride solution is added to the reaction mixture, and the resulting product is extracted with a solvent such as dichloromethane, dried and then concentrat¬ ed under reduced pressure to obtain a solid product which is then directly recrystallized or, if necessary, purified with distillation or column chromatography to obtain the desired compound of formula (Ila) . Typical examples of the compound of formula (Ila) which can be obtained by the reaction (a) above are as follows : - 2-(l-hydroxypentyl) -1, 4 , 5, 8-tetramethoxynaphthalene, 2-(l-hydroxyhexyl) -1,4,5, 8-tetramethoxynaphthalene, 2- (1-hydroxyocty1) -1,4,5, 8-tetramethoxynaphthalene, 2- (l-hydroxydecyl) -1,4 , 5,8-tetramethoxynaphthalene, and 2- (1-hydroxytridecy1) -1,4,5, 8-tetramethoxynaphthalene. In the above reaction (b) for preparing the compound of formula (II) , the compound of formula (Ila) is alkylated to prepare the compound of fo rula (lib) . This reaction (b) is preferably carried out in the presence of a solvent. As a suitable solvent for this purpose, conventional aprot- ic solvents, for example, tetrahydrofuran, acetonitrile, etc. , can be preferably used. The alkylating agent which can be used in this reaction includes a conventional alky- lating agent such as alkyl iodide, alkyl bromide, dialkyl sulfate, etc., with alkyl bromide being particularly pref¬ erable. Specifically, according to the preferred embodiment of the reaction (b) of the present invention, the compound of formula (Ila) and sodium hydride preferably in 1 to 10 times molar amount, particularly in 2 to 5 times molar amount, with respect to the compound (Ila) are dissolved in a suitable solvent, and then to the resulting solution are added sodium hydride and an aquimolar amount of the alky- lating agent. The reaction mixture is then refluxed preferably for 1 to 10 hours, particularly for 1 to 3 hours. When the reaction is completed, ice-water is added to the reaction solution, and the mixture is extracted with a solvent such as dichloro ethane, dried and then concen¬ trated. The resulting crystalline product is treated according to the conventional working-up procedure, for example, by purifying the crystal with recrystallization from hexane and, if necessary, further purifying the product with a conventional technique, for example, distil¬ lation or column chromatography. Typical examples of the compound of formula (lib) which can be prepared according to the above reaction (b) are as follows : 2- (l-ethoxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaphtha- lene, 2-[l-(3-methylbutoxy) -4-methylpentyl]-1, 4 , 5, 8-tetrameth- oxynaphthalene, 2-(l-pentyloxy-4-methylpentyl) -1,4, 5,8-tetramethoxynaph- thalene, - 2-(l-heptyloxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaph- thalene, and - 2-(l-dodecyloxy-4-methylpentyl) -1,4,5, 8-tetramethoxynap- hthalene . According to the above reaction (c) for preparing the compound of formula (II) , the compound of formula (Ila) is acylated with the compound of formula RCOOH to prepare the compound of formula (lie) . The acylation reaction according to the reaction (c) is preferably carried out in the presence of an organic base and dicyclohexylcarbodiimide (DCC) . The base which can be used for this purpose includes an amine compound, for example, dimethylamine, diethylamine, triethylamine, etc. , pyridine, or dialkylamino pyridine, for example, 4- dimethylaminopyridine, etc., with 4-dimethylaminopyridine being particularly preferable. In addition, the acylation reaction can be carried out in the presence of a suitable solvent. As the solvent suitable for this purpose, op¬ tionally chlorinated hydrocarbon solvents can be used. Among them, dichloromethane, chloroform, methylene chlo¬ ride, etc. can be preferably used, with dichloromethane being particularly preferable. As typical example of the compound of formula (He) which can be prepared according to the reaction (c) , 2-(l- acetoxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaphthalene can be mentioned. Method B According to the method B for preparing the compound of formula (I) of the present invention, the compound of formula (I) wherein R 3 is alkyl, i.e. the compound of formula (la) , which can be prepared by the method A above, can be dealkylated to prepare the compound of formula (I) wherein R is hydrogen, i.e. the compound of formula (lb) . A dealkylating agent which can be used in this reac¬ tion can include boron tribromide, HCl-pyridine, aluminum chloride, silver oxide-nitric acid compound, etc. The particularly preferable dealkylating agent is silver oxide- 5 nitric acid compound. In the preferred embodiment for carrying out the method B of the present invention, the compound of formula (la) is dissolved in a reaction-inert organic solvent such 10 as acetone, benzene, toluene, etc. , and then to the result¬ ing solution is added the dealkylating agent preferably in 1 to 10 times molar amount, particulalrly in 2 to 6 times molar amount, with respect to the compound of formula (la) . The reaction mixture is then stirred preferably at 1 to 15 50°C, particularly at room temperature, preferably for 1 to 10 hours, particularly for 3 to 4 hours, and extracted with a suitable extracting solvent such as dichloromethane, etc. The extract is dehydrated with a drying agent, evaporated and then concentrated. If required, the resulting product 20 can be separated and purified according to conventional working-up procedures such as recrystallization, column chromatography, and the like. As typical example of the compound of formula (lb) 25 which can be prepared by the method B of the present inven¬ tion the following compounds can be mentioned : 2-(l-hydroxypentyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-hydroxyhexyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 30 ~ 2- (1-hydroxyoctyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2-(l-hydroxydecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2-(1-hydroxytridecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2-(l-acetoxy-4-methylpentyl) -5, 8-dihydroxy-l, 4-naphthoq- uinone, 35 - 2-(l-ethoxy-4-methylpentyl) -5,8-dihydroxy-l, 4-naphthoqu- inone, - 2-[l-(3-methylbutoxy) -4-methylpentyl]-5, 8-dihydroxy-l,4- naphthoquinone, 2-(l-pentyloxy-4-methylpentyl) -5, 8-dihydroxy-l, 4-naphth¬ oquinone, 2-(l-heptyloxy-4-methylpentyl) -5,8-dihydroxy-l, 4-naphth- oquinone, and 2-(l-dodecyloxy-4-methylpentyl) -5, 8-dihydroxy-l, 4-napht- hoquinone. Method C According to the method C for preparing the compound of formula (I) of the present invention, the compound of formula (I) wherein R is hydrogen, i.e. the compound of formula (Ic) , which can be prepared by the method A above, can be acylated with an organic acid of formula RCOOH to prepare the compound of formula (I) wherein R 2 is acyl group -C(0)R, i.e. the compound of formula (Id) . The acylation reaction according to the method C is preferably carried out in the presence of an organic base and dicyclohexylcarbodii ide (DCC) . The base which can be used in the method C includes an amine compound, for example, dimethylamine, diethylamine, triethylamine, etc., pyridine, or dialkylamino pyridine, for example, 4-dimethylaminopyridine, etc., with 4-dimeth- ylaminopyridine being particularly preferable. In addi¬ tion, the acylation reaction can be carried out in the presence of a suitable solvent. As the solvent suitable for this purpose, optionally chlorinated hydrocarbon sol¬ vents can be used. Among them, dichloromethane, chloro¬ form, carbon tetrachloride, etc. can be preferably used, with dichloromethane being particularly preferable. In the preferred embodiment for carrying out the method C of the present invention, dicyclohexylcarbodiimide and the organic base are used in an amount of 1.0 to 2.0 mole and 0.01 to 0.5 mole, respectively, with respect to one mole of the compound of formula (Ic) . In addition, the amount of the solvent used in this reaction is prefera- bly 8 to 15 times the amount of the compound of formula (Ic) . The compound (Ic) and the compound of formula RCOOH are reacted together with stirring in the presence of nitrogen gas at -5 to +5°C for first 30 minutes and then the reaction solution is warmed to 15 to 30°C and stirred for 1 to 3 hours. When the reaction is completed, to the reaction mixture is added n-hexane in an amount of about 100 times the amount of the compound of formula (Ic) to precipitate the insoluble material which is then filtered off. The filtrate is concentrated and then, if necessary, the synthesized product is purified by means of silica gel chromatography, gel filtration and the like. As typical example of the compound of formula (I) which can be prepared by the method C of the present inven- tion the following compounds can be mentioned : 2-(l-acetoxyhexyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-hexanoyloxyhexyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-octanoyloxyhexyl) -5, 8-dihydroxy-l, 4-naphthoquinone, - 2-[l-(3-trans-hexenoyloxy) -hexyl]-5, 8-dihydroxy-l ,4-nap- hthoquinone, 2-(l-acetoxy-4-methylpentyl) -5, 8-dihydroxy-l, 4-naphthoq- uinone, 2- (l-hexanoyloxy-4-methylpentyl) -5, 8-dihydroxy-l,4-naph- thoquinone, 2- (l-octanoyloxy-4-methylpentyl) -5, 8-dihydroxy-l, 4-naph- thoquinone, 2-[l- (3-trans-hexenoyloxy) -4-methylpentyl]-5, 8-dihydroxy -1, 4-naphthoquinone, - 2- (1-acetoxyoxydecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-hexanoyloxydecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-octanoyloxydecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2-[l- (3-trans-hexenoyloxy) -decyl]-5, 8-dihydroxy-l, 4-nap¬ hthoquinone, 2- (1-acetoxytridecyl) -5, 8-dihydroxy-l, 4-naphthoquinone, 2- (1-butanoyloxytridecyl) -5, 8-dihydroxy-l, 4-naphthoquin- one, and 2- (1-hexanoyloxytridecyl) -5, 8-dihydroxy-l, 4-naphthoquin- one. The compound of formula (I) which can be prepared by the above methods A to C according to the present inven¬ tion, excluding some known compounds, is a novel compound. Such novel compound is also the subject of the present invention. Accordingly, in another aspect, the present invention relates to a novel 5 , 8-dihydronaphthoquinone derivative represented by the following general formula (IA) : in which R J represents alkyl or alkenyl, R 2a represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be substituted or unsubstituted with one or more halogen(s) , and R represents hydrogen or alkyl, p. - provided that when R ώα is hydrogen or a group -C(0)R and R is hydrogen, R is other than 3-methyl-2-butenyl; and when R 2a and R 3 independently of one another represent hydrogen or methyl, R is other than 3-methylbutyl. Among the novel compound of formula (IA) according to the present invention, the preferred compounds are those wherein R 1 represents C 1 -C 15 alkyl or C 2 -C 15 alkenyl, R represents hydrogen, c ι~C 15 alkyl or a group -C(0)R wherein R represents C 1 -C 15 alkyl, C 2 -C 15 alkenyl, phenyl, phenyl- C 1 ~C 15 alkyl or phenyl-C 2 -C 15 alkenyl, which can be substi- 3 tuted or unsubstituted with one or more halogen(s) , and R p•= represents hydrogen or C^-Cg alkyl, provided that when R" l •S hydrogen or a group -C(0)R and RT is hydrogen, RI i-s other than 3-methyl-2-butenyl; and when R a and R 3 inde- pendently of one another represent hydrogen or methyl, R is other than 3-methylbutyl. As previously described, the purpose of the study of 5, 8-dihydronaphthoquinone derivatives by the present inven- tors resides in development of an anticancer agent having an excellent activity. Further, anticancer activity of 5 , 8-dihydronaphthoquinone derivatives according to the present invention could be evidently demonstrated from the cytotoxicity test, and the like. Accordingly, the use of "the novel 5, 8-dihydronaphthoquinone derivative of formula (IA) above as an anticancer agent is also included within the scope of the present invention. Cancer as one of current typical incurable diseases is difficult to completely cure because the kind of cancer and the cause of an attack of cancer are very diverse and, in most cases, the definite cancer attacking mechanism has not been established. Accordingly, numerous novel synthetic materials and natural substances have been examined for their possibility of treating cancer. The study of anticancer activity of shikonin, which is the parent compound of 5, 8-dihydronaphthoquinone derivative of formula (IA) according to the present invention, was conducted first by U. Sankawa [Chem. Pharm. Bull. 25, 2392- 2395 (1977)]. According to this test for effect of shiko¬ nin in mouse, it has been reported that shikonin shows an increase in life span (LSI) of 92% in mouse suffering from S-180 ascitic cancer while does not show a significant effect in mouse suffering from L1210 cancer. 5 Meanwhile, the present inventors have identified that the ether extract of Alkanna tinctoria shows a potent cytotoxic activity against leukemic cell lines L1210 (Kor. J. Pharmacogn. , 17, 186 (1986)) . We have isolated and identified those effective components and then disclosed Q that one of such effective components is acetylshikonin, which has ED 50 value of O.Olμg/ l against L1210 cells and LSI of 85% in mouse suffering from S-180 sarcoma (Kor. J. Pharm. Soc. , 34, 262-266 (1990)) . 5 According to this, the present inventors have observed a cytotoxic effect on L1210, HL-60, K562 and A549 cells and a LSI effect in mouse suffering from S-180 sarcoma, of the 5, 8-dihydronaphthoquinone derivative of the present inven¬ tion. In the cytotoxicity test, a chemotherapeutic agent, 0 5-fluorouracil, which has been most widely used for treat¬ ing cancer in clinical field and has been recognized as having a good cytotoxicity was used as a comparative drug; and in the test for LSI effect the currently used antican¬ cer agent, doxorubicin was used as a comparative drug. 5 This is based on the assumption that since the structure of acylshikonin derivatives is similar to that of adriamycin which acts as an inhibitor of DNA intercalator and DNA topoisomerase type 1, the action of shikonin will be simi¬ lar to that of adriamycin. 0 On the basis of the results from the tests for cyto¬ toxicity and LSI effect, it could be identified that the novel 5, 8-dihydronaphthoquinone derivative of formula (IA) according to the present invention has an excellent cyto- 5 toxicity and anticancer activity and therefore can be used as a clinically useful anticancer agent. When the com¬ pound of the present invention is used in clinical purpose, this compound can be used in the form of a suitable formu¬ lation which is conventional in the pharmaceutical field. Accordingly, the present invention also relates to a phar¬ maceutical composition for treating cancer which contains the novel 5, 8-dihydronaphthoquinone derivative of formula (IA) as an active ingredient. The pharmaceutical composition of the present inven¬ tion can be prepared in a pharmaceutically conventional formulation, for example, formulations for oral administra¬ tion such as tablets, capsules, troches, solutions, suspen¬ sions, and the like, injectable formulations such as in- jectable solution or suspension or ready-to-use injectable dry powder which can be used by reconstituting with dis- tilled water for injection just before injection, or topi¬ cally applicable formulations such as ointments, creams, solutions, and the like, using a conventional carrier according to the conventional pharmaceutical methods. The carriers which can be used for this purpose in¬ clude those conventionally used in pharmaceutical field, for example, binders, lubricants, disintegrants, excipi- ents, solubilizing agents, dispersing agents, stabilizers, suspending agents, coloring agents, perfumes, etc., in the case of oral preparation, preservatives, painless agents, solubilizing agents, stabilizers, etc. , in the case of injectable preparation, and bases, excipients, lubricants, preservatives, etc., in the case of preparation for topical use. The pharmaceutical formulation thus prepared can be administered orally or parenterally, for example, intrave¬ nously, subcutaneously, intraperitoneally, etc. , or can topically apply. In addition, when the preparation is administered per oral, it can be preferably administered together with antacids or in the form of an enteric-coated formulation such as enteric-coated tablets. Although the dosage of the 5 , 8-dihydronaphthoquinone derivative of formula (IA) according to the present inven¬ tion for human is appropriately selcted depending on the absorption, inactivation and secretion of the active compo¬ nent in the human body, age, sex and condition of patients, kind and severity of cancer to be treated, etc., the dosage is generally in the range of 20 to 200mg, preferably in the range of 50 to 150mg, per a day in adult patient. Howev¬ er, it should be uderstood that the dosage as mentioned above can be appropriately increased or reduced using a specialized dosage regimen according to the judgement of specialists who supervise or observe the administration of drug and individual request in the case of a certain type of cancer. The effective daily dose of the active ingre¬ dient can be administered as a single dose or a multiple- divided dose, preferably over 3 to 6 times, at regular intervals. The preparation of 5, 8-dihydronaphthoquinone deriva¬ tives of formula (I) according to the process of the present invention will be more specifically illustrated in the following examples. However, it should be understood that the present invention will not be limited to these examples in any manner. EXAMPLE 1 : Preparation of 2- fl-acetyloxy-4-methyl-3-pente- nyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 60mg (1 mmole) of acetic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room te per- ature for further 3 hours. 20ml of n-hexane was added to the reaction solution. The mixture was filtered to remove the insoluble materials. The filtrate was dried and then concentrated under reduced pressure. The residue was purified with silica gel column chromatography (n-hexane: ethylacetate=20: 1-5: 1) to obtain 247mg (Yield: 75%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , S ppm) : 12.58(s, IH) , 12.42(s, IH) , 7.18(s, 2H) , 6.99(d, J=l.lHz, IH) , 6.00(m, IH) , 5.12(m, IH) , 2.51(m, 2H) , 2.13(s, 3H) , 1.69(s, 3H) , 1.57(s, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.2, 176.7, 169.7, 167.5, 167.0, 148.2, 136.1, 132.9, 132.7, 131.5, 117.7, 111.7, 111.0, 69.4, 32.8, 25.7, 21.1, 17.9 IR : 2925, 1740, 1605, 1450 MASS (rel. int.) : 330(M + , 2) , 270(100) , 255(43) , 228(9), 220(71), 219(89), 163(4), 137(3), 84(47) EXAMPLE 2: Preparation of 2- (l-monochloroacetyloxy-4-meth yl-3-pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- ro ethane. To the resulting solution was added 94.5mg (1 mmole) of monochloroacetic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedure as described in Example 1 to obtain 218mg (Yield: 60%) of the title compound having the following structure as a red oil. 1 H-NMR (CDC1 3 , δ ppm) : 12.57(s, IH) , 12.40(s, IH) , 7.17(s, 2H) , 7.04(s, J=l.lHz) , 6.07 (in, IH) , 5.07(m, IH) , 4.09(s, 2H) , 2.58(m, 2H) , 1.65(s, 3H) , 1.54(s, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 176.5, 174.9, 168.8, 168.3, 166.1, 146.6, 136.6, 133.4, 133.1, 131.2, 117.1, 111.7, 111.5, 71.2, 40.6, 32.7, 25.7, 17.9 IR : 2925, 1750, 1605, 1450 MASS (rel. int.) : 365(M + , 3) , 296(3) , 271(40), 270(100) , 255(46), 220(49) , 219(30) , 191(7) , 149(10), 84(17) EXAMPLE 3 : Preparation of 2- (l-trichloroacetyloxy-4-meth- yl-3-pentenyl) -5 , 8-dihydroxy-l , 4-naphthoguinόne 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 163mg (1 mmole) of trichloroacetic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 398mg (Yield: 92%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.68(s, IH) , 12.49(s, IH) , 7.29(s, 2H) , 7.26(d, J=1.0Hz, IH) , 6.28(m, IH) , 5.26(m, IH) , 2.81(m, 2H) , 1.80(s, 3H) , 1.71(s, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 174.9, 173.2, 170.4, 169.9, 160.7, 145.1, 137.3, 134.0, 133.7, 130.8, 116.5, 111.8, 111.6, 89.5, 74.4, 32.9, 25.8, 18.0 IR : 2920, 1765, 1610, 1230 MASS (rel. int.) : 433(M + , 0.5) , 366(4) , 364(5) , 270(89) , 255(42) , 228(8) , 219(5) , 191(4) , 120(25) , 86(66) , 84(100) , 69(92) EXAMPLE 4 : Preparation of 2- (l-n-propionyloxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 74mg (1 mmole) of n-propionic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 210mg (Yield: 61%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ p P m) : 12.58(s, IH) , 12.42(s, IH) , 7.18(s, 2H) , 6.98 (d, J=1.0HZ, IH) , 6.02(m, IH) , 5.12(m, IH) , 2.52 (m, 2H) , 2.42(q, J=7.7Hz, 2H) , 1.69(s, 3H) , 1.58(s, 3H) , 1.18(t, J=7.7HZ, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 173.1, 167.3, 166.8, 148.4, 136.0, 132.8, 132.6, 131.4, 117.7, 111.8, 111.5, 69.2, 32.8. 27.6, 25.7, 17.9, 9.0 IR : 2910, 1740, 1610, 1450 MASS (rel. int.) : 344(M + , 0.5) , 310(9) , 271(29) , 270(72) , 220(49) , 219(40) , 189(13) , 149(10) , 137(11) , 91(32) , 77(18) , 57(100) EXAMPLE Preparation of 2- ( l-n-butanoyloxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethyla inopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 88mg (1 mmole) of n-butanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 186mg (Yield: 52%) of the title compound having the following structure as a red oil. ^ • H-NMR (CDC1 3 , δ ppm) : 12.59(s, IH) , 12.43(s, IH) , 7.19(s, 2H) , 6.99(S, J=0.9Hz, IH) , 6.04(m, IH) , 5.13(m, IH) , 2.52 (m, 2H) , 2.38(t, J=7.5Hz, 2H) , 1.69(s, 3H) , 1.58(Ξ, 3H) , 1.26(m, 2H) , 0.97(t, J=7.5Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 172.3, 167.3, 166.7, 148.4, 135.9, 132.8, 132.6, 131.4, 117.8, 111.8, 111.5, 69.2, 36.1, 32.9, 25.7, 18.4, 17.9, 13.6 IR : 2950, 1740, 1610, 1450 MASS (rel. int.) : 358(M + , 1) , 340(3) , 270(29) , 255(16) , 220(13) , 190(4) , 137(6) , 108(6) , 91(6) , 71(100) , 43(100) EXAMPLE 6 : Preparation of 2- (l-isobutanovioxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethyla inopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 88mg (1 mmole) of isobutanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 161mg (Yield: 45%) of the title compound having the following structure as a red oil. 1 H-NMR (CDC1 3 , δ ppm) : 12.58(s, IH) , 12.42(s, IH) , 7.18(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.01(m, IH) , 5.12(m, IH) , 2.75- 2.45(m, 3H) , 1.69(s, 3H) , 1.58(s, 3H) , 1.21(d, J=7.7Hz, 6H) 13 C-NMR (CDC1 3 , <5 ppm) : 178.3, 176.8, 175.8, 167.3, 166.8, 148.5, 136.0, 132.8, 132.6, 131.3, 117.8, 111.8, 111.6, 69.0, 34.0, 33.0, 25.7, 18.9, 18.8, 18.0 IR : 2950, 1740, 1610, 1450 MASS (rel. inf.) : 358(M + , 2), 288(2) , 271(50) , 270(58) , 255(26), 220(21) , 189(6) , 137(5) , 89(5) , 71(100) EXAMPLE 7 : Preparation of 2- (l-n-hexanoyloxy-4-methyl-3- pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- di ethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 116mg (1 mmole) of n-hexanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 150mg (Yield: 39%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.50(Ξ, IH) , 12.34(s, IH) , 7.09(s, 2H) , 6.91(d, J=0.8Hz, IH) , 5.96(m, IH) , 5.05(m, IH) , 2.44(m, 2H) , 2.32(t, J=7.2Hz, 2H) , 1.62(s, 3H) , 1.51(s, 3H) , 1.35-0.76(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.7, 172.5, 167.3, 166.8, 148.4, 135.9, 132.8, 132.6, 131.4, 117.8, 111.8, 111.5, 69.2, 34.2, 32.9, 31.2, 25.7, 24.6, 22.3, 17.9, 13.8 IR : 2950, 1740, 1610, 1450 MASS (rel. int.) : 386(M + , 0.5) , 288(2) , 271(16), 270(55) , 255(16), 220(14) , 190(2) , 99(100), 71(31) , 60(16) EXAMPLE 8 Preparation of 2-f 1- (4-pentenoyl) oxy-4-methyl-3 -pentenyl1-5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added lOOmg (1 mmole) of 4-pentenoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 155mg (Yield: 42%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , <S ppm) : 12.48(s, IH) , 12.32(Ξ, IH) , 7.08(s, 2H) , 6.90(d, J=1.1HZ, IH) , 6.05-5.60(m, 2H) , 5.15-4.85(m, 3H) , 2.60-2.30(m, 6H) , 1.61(s, 3H) , 1.50(s, 3H) 13 C-NMR (CDC1 3 , tS ppm) : 178.1, 176.6, 171.7, 167.4, 166.9, 148.2, 136.3, 136.0, 132.8, 132.6, 131.5, 117.8, 115.8, 111.8, 111.5, 69.4, 33.4, 32.9, 28.7, 25.7, 17.9 IR : 2910, 1740, 1610, 1450 MASS (rel. int.) : 370(M + , 3) , 271(100) , 270(100) , 255(58) , 220(49) , 190(10) , 163(5) , 137(8) , 108(9) , 83(100) , 55(100) EXAMPLE 9 : Preparation of 2-F 1- (3 , 3-dimethyl) acryloxy-4- methyl-3-pentenyll -5 , 8-dihvdroxy-l , 4-naphtho¬ quinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added lOOmg (1 mmole) of 3 , 3-dimethylacrylic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the proce¬ dures as described in Example 1 to obtain 229mg (Yield: 62%) of the title compound having the following structure as a red precipitate. L H-NMR (CDC1 3 , δ ppm) : 12.59(s, IH) , 12.42(s, IH) , 7.27(s, 2H) , 6.97(d, J=l.lHz, IH) , 6.00(m, IH) , 5.79(s, IH) , 5.14(m, IH) , 2.51(m, IH) , 2.15(s, 3H) , 1.93(s, 3H) , 1.68(Ξ, 3H) , 1.56(s, 3H) 13 ! ,C-NMR (CDC1 3 , δ ppm) : 179.0, 177.5, 166.8, 165.3, 158.9, 149.0, 135.8, 132.6, 132.4, 131.6, 118.0, 115.3, 111.9, 111.6, 68.6, 60.4, 32.9, 27.7, 25.7, 20.3, 18.0 IR : 2900, 1720, 1605, 1450 MASS (rel. int.) : 392(M + , 1) , 353(4) , 270(34) , 254(3) , 83(100) EXAMPLE 10 Preparation of 2- (l-phenylacetyloxy-4-methyl-3 -pentenyl -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethyla inopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 136mg (1 mmole) of phenylacetic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 239mg (Yield: 59%) of the title compound having the following structure as a red precipitate. 12.55(Ξ, IH) , 12.39(Ξ, 3H) , 7.45-7.30(m, 5H) , 7.17(s, 2H) , 6.78(d, J=0.9Hz, IH) , 6.02(m, IH) , 5.03(m, IH) , 3.69(s, 2H) , 2.48(m, 2H) , 1.64(s, 3H) , 1.53(s, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 177.9, 176.5, 170.2, 167.5, 166.9, 147.9, 136.0, 133.5, 132.9, 132.6, 131.3, 129.2, 128.7, 127.3, 117.6, 111.8, 111.5, 69.8, 41.5, 32.8, 25.7, 17.8 IR = 2925, 1740, 1605, 1450 MASS (rel. int.) : 406(M + , 3) , 388(8) , 271(22) , 270(98) , 255(20) , 220(20) , 219(16) , 136(16) , 118(25) , 91(100), 84(25) , 69(16) EXAMPLE 11 : Preparation of 2-f l-trans- f2-hexenoyl) oxy-4- methyl-3-pentenyl] -5 , 8-dihydroxy-l , 4-naphtho¬ quinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 114mg (1 mmole) of trans-2-hexenoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 150mg (Yield: 38%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.59(s, IH) , 12.43(s, IH) , 7.28-6.90(m, IH) , 7.18(s, 2H) , 6.99(d, J=1.0Hz, IH) , 6.20-5.80(m, 2H) , 5.14(m, IH) , 3.47(q, J=7.2Hz, 2H) , 2.80- 1.70(m, 15H) 13 C-NMR (CDC1 3 , δ ppm) : 178.7, 177.2, 167.0, 166.5, 165.3, 150.9, 148.6, 135.0, 132.7, 132.5, 131.6, 120.6, 117.8, 111.8, 111.5, 69.2, 34.3, 32.9, 39.7, 29.2, 17.9, 13.7 IR : 2900, 1720, 1610, 1450 EXAMPLE 12 Preparation of 2-fl-trans- (3-hexenoyl) oxy-4- methyl-3-pentenyl1 -5 , 8-dihvdroxy-l , 4-naphtho- σuinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- di ethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 114mg (1 mmole) of trans-3-hexenoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 115mg (Yield: 30%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.16(s, 2H) , 6.98(d, J=0.9Hz, IH) , 6.02(m, IH) , 5.85-5.30(m, 2H) , 5.13(s, IH) , 3.10(d, J=5.5Hz, 2H) , 2.56(m, 2H) , 2.07(m, 2H) , 1.69(Ξ, 3H) , 1.59(s, 3H) , 1.01(t, J=7.2Hz, 3H) 13 C-NMR (CDCI3, <S ppm) : 178.2, 176.7, 170.8, 167.4, 166.8, 148.2, 136.9, 136.0, 132.8, 132.6, 131.4, 119.9, 117.7, 111.8, 111.5, 69.5, 38.0, 32.8, 25.7, 25.5, 17.9, 13.4 IR : 2950, 1740, 1605, 1450 EXAMPLE 13 : Preparation of 2- r 1- (6-heptenoyl) oxy-4-methyl- 3-pentenyII -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 128mg (1 mmole) of 6-heptenoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 175mg (Yield: 44%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.39(s, IH) , 7.15(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.15-5.65(m, 2H) , 5.13-4.89 (m, 3H) , 2.80-2.00(m, 6H) , 1.69(s, 3H) , 1.58(s, 3H) , 2.80- 1.50(m, 2H) 13 C-NMR (CDC1 3 , δ ppm) : 178.1, 17 ' 6.6, 172.2, 167.3, 166.7, 148.3, 138.1, 135.8, 132.7, 132.5, 131.3, 117.8, 114.7, 111.7, 111.4, 34.0, 33.2, 32.8, 28.2, 25.6, 24.3, 17.8 IR : 2925, 1740, 1605, 1450 EXAMPLE 14 : Preparation of 2- (l-n-octanoyloxy-4-methyl-3- pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 144mg (1 mmole) of n-octanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 174mg (Yield: 42%) of the title compound having the following structure as a red oil. ^-H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.38(s, IH) , 7.15(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.03(m, IH) , 5.13(m, IH) , 2.51(m, 2H) , 2.40(t, J=7.5Hz, 2H) , 1.69(s, 3H) , 1.58(s, 3H) , 1.50-1.10(m, 10H) , 0.88(t, J=6.0Hz, 3H) 178.3, 176.8, 172.4, 167.1, 166.6, 148.4, 135.8, 132.6, 132.5, 131.4, 117.8, 111.7, 111.5, 69.1, 34.2, 32.8, 31.6, 29.0, 28.8, 2'5.6, 24.8, 22.5, 17.8, 13.9 IR : 2925, 1740, 1610, 1450 EXAMPLE 15 : Preparation of 2- (l-n-nonanoyloxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 158mg (1 mmole) of n-nonanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 23lmg (Yield: 54%) of the title compound having the following structure as a red oil. 1 H-NMR (CDC1 3 , δ ppm) : 12.54(s, IH) , 12.38(s, IH) , 7.15(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.03(m, IH) , 5.13(m, IH) , 2.51(m, 2H) , 2.39(t, J=7.2Hz, 2H) , 1.68(s, 3H) , 1.58(s, 3H) , 1.50-1.10(m, 12H) , 0.87(t, J=6.3Hz, 3H) 178.2, 176.8, 172.4, 167.2, 166.6, 148.4, 135.8, 132.6, 132.5, 131.4, 117.8, 111.7, 111.4, 69.1, 34.2, 32.8, 31.7, 31.4, 29.1, 29.0, 25.6, 24.8, 22.5, 17.8, 13.9 IR : 2925, 1740, 1610, 1450 EXAMPLE 16 Preparation of 2-(l-n-decanoyloxy-4-methyl-3- pentenyl) -5, 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 172mg (1 mmole) of n-decanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 217mg (Yield: 49%) of the title compound having the following structure as a red oil. ^-H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.39(s, IH) , 7.15(s, 2H) , 6.98(d, J=0.9Hz, IH) , 6.03(m, IH) , 5.13(m, IH) , 2.52(m, 2H) , 2.40(t, J=7.3Hz, 2H) , 1.69(s, 3H) , 1.59(s, 3H) , 1.50-1.10(m, 14H) , 0.88(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 172.4, 167.2, 166.7, 148.4, 135.8, 132.7, 132.5, 131.4, 117.8, 111.8, 111.5, 69.1, 34.2, 32.9, 31.8, 29.3, 29.2, 29.1, 29.0, 25.6, 24.9, 22.6, 17.8, 14.0 IR : 2925, 1740, 1610, 1450 EXAMPLE 17 : Preparation of 2- fl-lauryloxy-4-methyl-3-pen- tenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 200mg (1 mmole) of lauric acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper- ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 202mg (Yield: 43%) of the title compound having the following structure as a red pre¬ cipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.57(s, IH) , 12.41(s, IH) , 7.17(m, IH) , 6.98(d, J=0.9Hz, IH) , 6.02(m, IH) , 5.12(m, IH) , 2.51(m, 2H) , 2.39(t, J=7.5Hz, 2H) , 1.68(s, 3H) , 1.58(s, 3H) , 1.55-1.10(m, 18H) , 0.88(t, J=6.3Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.2, 176.7, 172.4, 167.4, 166.8, 148.4, 135.9, 132.8, 132.6, 131.4, 117.8, 111.8, 111.5, 69.2, 34.3, 32.9, 31.8, 31.5, 29.5(2C), 29.4, 29.2, 29.1, 25.7, 24.9, 22.6, 17.9, 14.0 IR : 2925, 1740, 1610, 1450 EXAMPLE 18 : Preparation of 2-(l-diphenylacetyloχy-4-meth- yl-3-pentenyl) -5 , 8-dihydroxy-l , 4-naphthoqui- none 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 212mg (1 mmole) of diphenylacetic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 270mg (Yield: 59%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , <S ppm) : 12.56(s, IH) , 12.38(s, IH) , 7.33(s, 10H) , 7.17(s, 2H) , 6.66(d, J=0.8Hz, . IH) , 6.09(m, IH) , 5.11(s, IH) , 5.04(m, IH) , 2.48(m, 2H) , 1.63(s, 3H) , 1.52(s, 3H) 177.7, 176.2, 171.1, 167.6, 167.1, 147.7, 138.1, 137.8, 136.0, 132.9, 131.2, 129.5, 129.4, 129.1, 129.0, 128.7, 128.6, 128.2, 127.7, 127.5, 127.4, 117.7, 111.7, 111.5, 70.0, 57.1, 32.9, 25.6, 17.8 IR : 2925, 1740, 1605, .1450 MASS (rel. int.) : 482(M + , 0.5.) , 293(6) , 270(14) , 168(28) , 167(100) , 166(40) , 152(25) , 149(44) , 127(11) , 105(10) , 86(29) , 84(53) , 71(28) , 55(46) EXAMPLE 19 : Preparation of 2- (l-undecylenoyloxy-4-methyl-3 -pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- ro ethane. To the resulting solution was added 184mg (1 mmole) of undecylenic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 172mg (Yield: 38%) of the title compound having the following structure as a red oil. ^-H-NMR (CDC1 3 , δ ppm) : 12.57(s, IH) , 12.41(Ξ, IH) , 7.16(s, 2H) , 6.95(d, J=l.lHz, IH) , 6.00(m, IH) , 5.70(m, IH) , 5.25- 4.80(m, 3H) , 2.50(m, 2H) , 2.40-0.83(m, 22H) 13C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 172.5, 167.4, 166.9, 148.4, 139.1, 135.9, 132.8, 132.6, 131.4, 117.8, 114.1, 111.8, 111.5, 69.2, 111.5, 69.2, 34.3, 33.7, 32.9, 29.7, 29.3, 29.2, 29.0, 28.8, 25.7, 24.9, 17.9 IR 2925, 1740, 1605, 1450 MASS (rel. int.) 454(M , 1) , 288(3) , 271(34) , 270(100) , 255(24) , 220(25) , 167(6) , 107(6) , 81(13) , 67(27) EXAMPLE 20 Preparation of 2- (l-stearyloχy-4-methyl-3-pen- tenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethyla inopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 284mg (1 mmole) of stearic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper- ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 305mg (Yield: 55%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.58(s, IH) , 12.42(s, 1H) , 7.17(s, 2H) , 6.98(d, J=1.0Hz, IH) , 6.04(m, IH) , 5.12(m, IH) , 2.52(m, 2H) , 2.39(t, J=7.6Hz, 2H) , 1.50-0.80(m, 33H) 13 C-NMR (CDCI3, <S ppm) : 178.43, 176.98, 172.5, 167.3, 166.7, 148.5, 135.9, 132.8, 132.6, 131.5, 117.8, 111.8, 111.5, 69.2, 34.3, 32.9, 32.7, 29.7, 29.5, 29.4, 29.3, 29.1, 25.7, 25.2, 24.9, 22.7, 17.9, 14.1 IR : 2925, 1740, 1610, 1450 EXAMPLE 21 : Preparation of 2- (l-palmityIoxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 256mg (1 mmole) of palmitic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper¬ ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 305mg (Yield: 58%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.65(s, IH) , 12.49(s, IH) , 7.05(s, 2H) , 6.98(d, J=l.lHz, IH) , 6.03(m, IH) , 5.12(m, IH) , 2.52 (in, 2H) , 2.39(t, J=7.7HZ, 2H) , 1.69(s, 3H) , 1.58(s, 3H) , 1.43-0.80(m, 29H) 178.3, 176.8, 172.5, 167.3, 166.8, 148.5, 136.0, 132.8, 132.6, 131.5, 117.8, 111.8, 111.5, 69.2, 34.3, 32.9, 31.9, 31.8, 29.7, 29.5, 29.4, 29.3, 29.1, 29.0, 26.0, 25.7, 25.5, 25.0, 24.9, 23.0, 17.9, 14.1 IR : 2920, 1740, 1605, 1450 EXAMPLE 22 : Preparation of 2-(l-oleyloxy-4-methyl-3-pente- nyl) -5,8-dihydroxy-l, 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 282mg (1 mmole) of oleic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper¬ ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 265mg (Yield: 48%) of the title compound having the following structure as a red oil. 1 H-NMR (CDC1 3 , <S ppm) : 12.58(s, IH) , 12.42(s, IH) , 7.18(s, 2H) , 7.08(d, J=l.lHz, IH) , 6.03(m, IH) , 5.34(m, 2H) , 5.12 (m, IH) , 2.51(m, 2H) , 2.39(t, J=7.5Hz , 2H) , 2.00(m, 4H) , 1.69(s, 3H) , 1.57(ε, 3H) , 1.56-0.85(m, 25H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 172.3, 167.1, 166.5, 148.4, 135.8, 132.6, 132.4, 131.4, 130.0, 129.6, 117.8, 111.7, 111.4, 69.1, 34.2, 32.8, 31.8, 29.7, 29.6, 29.4, 29.2, 29.1, 29.0, 27.1, 25.6, 24.8, 22.6, 17.8, 14.0 IR : 2925, 1740, 1605, 1450 MASS (rel. int.) : 552(M + , 2) , 288(3) , 271(28) , 270(100) , 255(22), 229(13) , 220(18) , 151(6) , 111(20) , 97(37) , 83(37) EXAMPLE 23 Preparation of 2- (l-linolenyloxy-4-methyl-3- pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 278mg (1 mmole) of linolenic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper- ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 230mg (Yield: 42%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.58(s, IH) , 12.43(s, IH) , 7.18(s, 2H) , 6.98(d, J=1.0Hz, IH) , 6.03(m, IH) , 5.43-5.12 (in, 7H) , 2.86-0.80(m, 31H) 173.2, 176.7, 172.4, 167.3, 166.7, 148.4, 135.9, 132.8, 132.6, 131.8, 131.4, 130.2, 128.2, 127.7, 127.0, 117.8, 111.8, 111.5, 69.1, 34.2, 32.9, 29.5, 29.1, 29.0, 27.1, 25.7, 25.5, 25.4, 25.1, 24.9, 24.6, 20.5, 17.9, 14.2 IR : 2925, 1740, 1605, 1450 MASS (rel. int-.) : 548(M + , 3) , 288(3) , 277(32) , 272(69) , 270(100) , 255(39) , 254(24) , 220(25) , 191(4) , 149(11) , 135(20) , 121(24) , 108(53) , 95(44) , 79(60) EXAMPLE 24 : Preparation of 2- r 1- (trans-retinoyloxy) -4- methyl-3-pentenyl1 -5 , 8-dihvdroxγ-l , 4-naph- tho uinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 300mg (1 mmole) of trans-retinoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 200mg (Yield: 35%) of the title compound having the following structure as a red precipitate. ^ • H-NMR (CDC1 3 , δ ppm) : 12.61(s, IH) , 12.43(s, IH) , 7.72(m, IH) , 7.17(ε, 2H) , 7.00(d, J=0.9Hz, IH) , 6.45-5.80(m, 5H) , 5.17(m, IH) , 4.30(m, IH) , 2.60-0.80(m, 30H) 13 C-NMR (CDC1 3 , δ ppm) : 178.8, 177.3, 166.6, 166.1, 165.6, 154.5, 148.8, 140.0, 137.5, 137.0, 135.6, 134.6, 132.4, 132.2, 131.6, 131.5, 130.7, 129.9, 129.7, 129.2, 128.8, 128.6, 117.9, 117.1, 111.7, 111.4, 68.6, 60.2, 39.4, 32.9, 32.8, 29.1, 28.8, 25.6, 24.6, 21.6, 21.3, 20.8, 19.3, 19.1, 17.8, 14.0, 13.8, 12.8 IR : 2925, 1710, 1605, 1450 MASS (rel. int.) : 570(M + , 100) , 444(12) , 300(18) , 299(20) , 272(11), 255(12), 29(16) , 205(22) , ' 201(19) , 189(24), 176(23) , 161(30) , 149(16) , 133(21) , 119(33), 99(47), 81(20) EXAMPLE 25 : Preparation of 2-r 1- (cis-retinoyl oxy-4-meth- yl-3-pentenyl1-5 , 8-dihydroxy-l , 4-naphthoqui- none 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 300mg (1 mmole) of cis-retinoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 217mg (Yield: 38%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.60(s, IH) , 12.42(s, IH) , 7.72(m, IH) , 7.16(s, 2H) , 6.98(d, J=0.8Hz, IH) , 6.40-5.70(m, 5H) , 5.17(m, IH) , 2.53(m, 2H) , 2.40-0.80(m, 28H) 13 C-NMR (CDC1 3 , <S ppm) : 178.8, 177.4, 166.8, 166.2, 164.9, 153.0, 148.9, 140.3, 137.6, 137.3, 135.7, 133.2, 132.9, 132.5, 132.3, 131.6, 130.1, 129.3, 129.0, 128.8, 118.0, 115.2, 111.8, 111.5, 68.7, 39.6, 34.2, 33.1, 32.8, 28.9, 25.7, 21.7, 21.0, 19.2, 17.9, 12.8 IR : 2925, 1710, 1605, 1450 EXAMPLE 26 : Preparation of 2- (l-n-pentanoyloxy-4-methyl-3- pentenyl) -5 , 8-dihydroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 102mg (1 mmole) of n-pentanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 223mg (Yield: 60%) of the title compound having the following structure as a red oil. ^-H-NMR (CDC1 3 , δ ppm) : 12.53(s, IH) , 12.37(s, IH) , 7.14(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.02(m, IH) , 5.13 (m, IH) , 2.70- 2.30(m, 4H) , 1.68(s, 3H) , 1.58(s, 3H) , 1.50- 1.10(m, 4H) , 0.93(t, J=6.2HZ, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.8, 172.3, 167.0, 166.4, 148.3, 135.7, 132.6, 132.4, 131.3, 117.8, 111.6, 111.4, 69.0, 33.9, 32.8, 26.8, 25.6, 22.1, 17.7, 13.5 IR : 2950, 1740, 1610, 1450 MASS (rel. int.) : 372(M + , 1) , 271(27), 270(59) , 220(21) , 85(100), 57(59) EXAMPLE 27 Preparation of 2-r1- (trans-2-pentenoyloxy) -4- methyl-3-pentenyll-5 , 8-dihydroxy-l , 4-naphtho- quinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added lOO g (1 mmole) of n-pentenoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 95mg (Yield: 23%) of the title compound having the following structure as a red precipitate. ^-H-NMR (CDC1 3 , δ ppm) : 12.58(s, IH) , 12.42(Ξ, IH) , 7.18(s, 2H) , 7.12(m, IH) , 7.00(d, J=1.0Hz, IH) , 6.08(m, IH) , 5.88(m, IH) , 5.14(m, IH) , 2.55(m, 2H) , 2.28(m, 2H) , 1.69(s, 3H) , l.ll(t, J=7.2Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.7, 177.2, 167.0, 166.5, 165.3, 152.2, 148.5, 135.9, 132.6, 132.5, 131.5, 119.6, 117.8, 111.8, 111.5, 69.2, 32.8, 25.7, 25.4, 17.9, 12.0 IR : 2925, 1720, 1610, 1450 MASS (rel. int.) : 370(M + , 2) , 288(6) , 271(49) , 270(100) , 255(65) , 220(14) , 137(4) , 97(13) , 83(100) EXAMPLE 28 Preparation of 2-[ 1- ( 2 , 4-hexadienoyloxy) -4- methγl-3-pentenyl1-5 , 8-dihydroxy-l , 4-naphtho- uinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo- romethane. To the resulting solution was added 112mg (1 mmole) of 2 , 4-hexadienoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 152mg (Yield: 40%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.57(s, IH) , 12.40(s, IH) , 7.30(m, IH) , 7.16(s, 2H) , 6.99(d, J=1.0HZ, IH) , 6.35-5.75(m, 4H) , 5.15(m, IH) , 2.56(m, 2H) , 1.86(d, J=5.1Hz, 3H) , 1.67(Ξ, 3H) , 1.58(s, 3H) 178.6, 177.2, 167.0, 166.4, 165.8, 148.5, 146.1, 140.3, 135.8, 132.6, 132.4, 131.5, 129.6, 118.1, 117.8, 111.8, 111.5, 69.2, 32.9, 25.7, 18.6, 17.9 IR : 2925, 1740, 1610, 1450 MASS (rel. int.) 382(M „+, 11) , 334(25) , 271(20) , 270(25) , 254(26) 229(16) , 112(78) , 97(100) , 67(60) EXAMPLE 29 Preparation of 2- \1- (trans-2 , 6-heptadienoyl- oxy) -4-methyl-3-pentenyll-5 , 8-dihydroxy-l , 4- naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 124mg (1 mmole) of 2 , 6-trans-heptanoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the proce¬ dures as described in Example 1 to obtain 125mg (Yield: 30%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.57(ε, IH) , 12.40(s, IH) , 7.15-7.00 (in, IH) , 7.17(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.20-5.60(m, 3H) , 5.30-4.80(m, 3H) , 2.90-2.10(m, 6H) , 1.68(s, 3H) , 1.57(s, 3H) 178.5, 177.0, 167.1, 166.6, 165.1, 149.8, 148.5, 136.8, 135.9, 132.7, 132.5, 131.5, 121.0, 117.8, 115.7, 111.6, 111.5, 69.3, 32.9, 31.9, 25.7, 17.9 IR : 2925, 1720, 1605, 1450 MASS (rel. int.) : 396(M + , 2) , 288(4) , 271(42) , 270(100) , 255(44) , 220(6) , 109(100) , 81(45) EXAMPLE 30 Preparation of 2-(l-benzoyloxy-4-methyl-3- pentenyl) -5 , 8-dihvdroxy-l , 4-naphthoquinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethylaminopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 122mg (1 mmole) of benzoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temper¬ ature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 117mg (Yield: 30%) of the title compound having the following structure as a red precipitate. 1 H-NMR (CDC1 3 , δ ppm) : 12.61(s, IH) , 12.40(s, IH) , 8.30-7.30(m, 5H) , 7.18(s, 2H) , 7.06(d, J=l.0Hz , IH) , 6.27(m, IH) , 5.22 (m, IH) , 2.68(m, 2H) , 1.69(s, 3H) , 1.61(s, 3H) 13 C-NMR (CDC1 3 -, δ ppm) : 177.9, 176.5, 167.7, 167.2, 165.3, 148.2, 136.2, 133.4, 132.9, 132.8, 131.4, 130.4, 129.7, 128.5, 117.7, 111.8, 111.0, 70.0, 33.0, 25.7, 18.0 IR : 2925, 1740, 1605, 1450 EXAMPLE 31 Preparation of 2- 1- ( 9 , 12-octadecadienoyloxy- 4-methyl-3-pentenyl1-5 , 8-dihydroxy-l , 4-naph- tho uinone 288mg (1 mmole) of shikonin, 226mg (1.1 mmole) of dicyclohexylcarbodiimide and 30mg (0.25 mmole) of 4- dimethyla inopyridine were dissolved in 3ml of dry dichlo¬ romethane. To the resulting solution was added 280mg (1 mmole) of 9 , 12-octadecadienoic acid at 0°C under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the proce¬ dures as described in Example 1 to obtain 210mg (Yield: 45%) of the title compound having the following structure as a red oil. 1 H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.40(s, IH) , 7.17(s, 2H) , 6.97(d, J=1.0Hz, IH) , 6.02(m, IH) , 5.38(m, 4H) , 5.12(m, IH) , 2.90-1.80(m, 10H) , 1.67(s, 3H) , 1.57(ε, 3H) , 1.50-0.70(m, 19H) 178.2, 17 * 6.7, 172.4, 167.3, 166.8, 148.4, 135.9, 132.7, 132.6, 131.4, 130.1, 129.9, 128.0, 127.8, 117.8, 111.8, 111.5, 69.1, 34.2, 32.9, 31.4, 29.5, 29.3, 29.0, 27.1, 25.7, 25.6, 24.8, 22.5, 17.9, 14.0 IR : 2920, 1740, 1605, 1450 EXAMPLE 32 : Preparation of 2- (1-hydroxypentyl) -5 , 8-dimet- hoxy-1 , 4-naphthoquinone 3.6g (10.3 mmole) of 2- (1-hydroxyhexyl) -1, 4 , 5, 8-tetra- methoxynaphthalene was disεolved in 50ml of acetonitrile and then a solution of 14.2g (25.0 mmole) of cerium (IV) ammonium nitrate dissolved in 50ml of distilled water was added dropwiεe thereto over 30 minuteε through a dropping funnel in a cooling bath (0-5°C) . The reaction mixture waε εtirred at normal temperature for 2 hourε. After adding 100ml of diεtilled water thereto, the reaction mixture waε extracted twice with dichloromethane εolvent, dried over anhydrouε magneεium εulfate and then filtered through filter paper. The reεulting filtrate waε concen¬ trated under reduced preεεure to obtain a crude product. The crude product was purified by silica gel column chroma¬ tography (silica gel 4.0 X 15cm) using the solvent condi¬ tion which increases the amount of ethylacetate so that the n-hexane/ethylacetate ratio can vary from 5:1 to 1:3, to obtain 1.2g of the title compound as a yellow precipitate. Yield : 48% TLC ( -hexane:ethylacetate=l:2) : Rf=0.34 Melting Point : 67.5-69.0°C ^-H-NMR (CDC1 3 , δ ppm) : 7.30(s, 2H) , 6.77(ε, IH) , 4.75(m, IH) , 3.95(ε, 6H) , 2.86(br.ε, IH) , 1.67(m, 2H) , 1.55-1.15 (m, 4H) , 0.89(t, J=6.0Hz, 3H) 13 C-NMR (CDCI3, <S ppm) : 185.3, 184.9, 153.8, 153.4, 151.2, 133.4, 121.1, 120.8, 120.5, 120.1, 69.1, 56.8, 56.7, 36.1, 27.9, 22.4, 13.9 IR : 3470, 2950, 1645, 1470 MASS : 304(M + , 62) , 289(100) , 275(65) , 257(24) , 247 (90) , 233(61) , 219(34) , 204(8) , 191(10), 173 (8) , 121(4) , 85(17) EXAMPLE 33 : Preparation of 2-(1-hydroxyhexyl) -5 , 8-dimeth- oxy-1 , 4-naphthoquinone According to the same procedure aε Example 32, 2-(l- hydroxyhexyl) -1, 4 , 5, 8-tetramethoxynaphthalene waε uεed to obtain 2. lg of the title compound aε a yellow oil. Yield : 64% TLC (n-hexane:ethylacetate=l:2) : Rf=0.19 1 H-NMR (CDC1 3 , δ ppm) : 7.30(s, 2H) , 6.76(d, J=l.lHz, IH) , 4.72(m, IH) , 3.95(s, 6H) , 2.90(d, J=5.4Hz, IH) , 1.66(m, 2H) , 1.55-1.10(m, 6H) , 0.87 (t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 185.2, 184.9, 153.7, 153.3, 151.2, 133.3, 121.0, 120.7, 120.4, 120.1, 68.9, 56.7, 56.6, 36.3, 31.4, 25.4, 22.4, 13.9 IR : 3475, 2925, 1645, 1470 MASS : 318(M + , 24) , 303(82), 289(40) , 257(19) , 247 (100), 233(33), 219(48), 204(29), 187(13), 173(10) " , 99(37) , 84(6) EXAMPLE 34 : Preparation of 2-(1-hydroxyoctyl) -5.8-dimeth- oχy-1.4-naphthoquinone According to the same procedure as Example 32, 2-(l- hydroxyoctyl) -1, 4 , 5, 8-tetramethoxynaphthalene was used to obtain 3.51g of the title compound aε a yellow precipitate. Yield : 40% TLC (n-hexane:ethylacetate=l:2) : Rf=0.39 ^-H-NMR (CDC1 3 , δ ppm) : 7.30(s, 2H) , 6.77(d, J=1.0Hz, IH) , 4.75(m, IH) , 3.94(s, 6H) , 2.99(br.ε, IH) , 1.61(m, 2H) , 1.50- 1.05(m, 10H) , 0.86(t, J=6.0HZ, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 185.2, 184.9, 153.7, 153.3, 151.4, 133.3, 120.7, 120.4, 120.1, 119.7, 68.8, 56.7, 56.6, 36.5, 31.7, 29.2, 29.0, 25.7, 22.5, 13.9 IR : 3475, 2925, 1645, 1560, 1470 MASS : 346(M + , 23) , 331(100) , 317(32) , 247(51) , 243 (15) , 219(13) , 205(5) , 84(11) , 57(2) EXAMPLE 35 Preparation of 2- (1-hvdroxydecyl) -5.8-dimeth- oxy-1 , 4-naphthoquinone According to the same procedure as Example 32, 2-(l- hydroxydecyl) -1 , 4 , 5 , 8-tetramethoxynaphthalene waε uεed to obtain 2.32g of the title compound aε a yellowish red oil. Yield : 60% TLC (n-hexane:ethylacetate=l: 2) : Rf=0.26 1 H-NMR (CDC1 3 , δ ppm) : 7.29(s, 2H) , 6.76(d, J=0.9Hz, IH) , 4.75(m, IH) , 3.94(s, 6H) , 2.86(br.ε, IH) , 1.70(m, 2H) , 1.55- 1.05(m, 1 ' 4H) , 0.86(t, J=6.0Hz, 3H) 185.2, 184.9, 153.7, 153.3, 151.4, 133.3, 121.0, 120.7, 120.4, 120.1, 68.8, 56.6(2C) , 36.5, 31.7, 29.4, 29.3(2C) , 29.1, 25.7, 22.5, 14.0 IR 3475, 2925, 1645, 1470 MASS 374(M + , 15) , 360(76) , 359(75) , 345(32) , 247 (100) , 233(27) , 219(29) , 204(12) , 191(7) , 84(21) EXAMPLE 36 : Preparation of 2- (1-hvdroxytridecyl) -5 , 8-dime- thoxy-1 , 4-naphthoquinone According to the εame procedure aε Example 32, 2-(l- hydroxytridecyl) -1, 4 , 5, 8-tetramethoxynaphthalene waε uεed to obtain 3. Og of the title compound as a yellow precipi- tate. Yield 71.5? TLC (n-hexane:ethylacetate=l: 2) : Rf=0.35 Melting Point : 91.7-93.2°C 1 H-NMR (CDC1 3 , δ ppm) : 7.30(s, 2H) , 6.78(d, J=l.lHz, IH) , 4.76(m, IH) , 3.95(s, 6H) , 2.89(d, J=5.0Hz, IH) , 1.63(m, 2H) , 1.50-1.15(m, 20H) , 0.88(t, J=6.1Hz, 3H) 185.3, 184.9, 153.8, 153.4, 151.3, 133.4, 121.1, 120.8, 120.4, 120.1, 69.0, 56.8, 56.7, 36.5, 31.8, 29.5, 29.4(5C) , 29.2, 25.8, 22.6, 14.0 IR : 3440, 2820, 1650, 1470 MASS : 416(M + , 28) , 401(100), 400(51), 387(37), 247 (48) , 233(11) , 219(10) , 191(2) , 57(2) EXAMPLE 37: Preparation of 2- (l-hydroxy-3-methyl-2-butenyl) -5, 8-dimethoxy-l ,4-naphthoquinone According to the εame procedure aε Example 32, 2-(l- hydroxy-3-methyl-2-butenyl) -1,4,5, 8-tetramethoxynaphthalene was used to obtain the title compound as a yellow precipi¬ tate. Yield : 48% TLC (n-hexane:ethylacetate=l: 2) : Rf=0.12 Melting Point : 168-170°C 7.29(ε, 2H) , 7.00-6.50(m, 3H) , 3.94(s, 6H) , 2.27(br.s, IH) , 1.41(s, 6H) 184.8, 184.5, 153.6, 153.1, 146.6, 143.7, 131.1, 121.6, 121.0, 120.1, 119.6, 118.4, 71.1, 56.7, 57.0, 29.4(2C) IR : 3470, 2970, 1650, 1475 MASS : 302(M + , 100) , 260(31) , 255(56) , 245(26) , 58(20) EXAMPLE 38 : Preparation of 2- (l-acetoxy-4-methylpentyI) - 5 , 8-dimethoxy-l , 4-naphthoquinone According to the same procedure as Example 32, 2-(l- acetoxy-4-methylpentyl) -1, 4 , 5, 8-tetramethoxynaphthalene was used to obtain the title compound aε a pale yellow precipi¬ tate. Yield : 45% TLC (n-hexane:ethylacetate=l: 2) : Rf=0.13 Melting Point : 125.5-127.0°C 1 H-NMR (CDC13, δ ppm) : 7.31(ε, 2H) , 6.65(ε, IH) , 3.95(s, 6H) , 2.11(s, 3H) , 2.00-1.10(m, 5H) , 0.87 (d, J=6.3Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 184.7, 183.5, 169.8, 154.1, 153.6, 149.5, 132.9, 121.2, 121.1, 120.6, 120.4, 70.0, 56.9, 56.8, 34.4, 32.5, 27.8, 22.6, 22.3, 20.9 IR : 2950, 1740, 1650, 1470 EXAMPLE 39 : Preparation of 2-(l-ethoxy-4-methylpentyl) - 5.8-dimethoxy-l .4-naphthoquinone 600mg (3.4 mmole) of 2- ( l-ethoxy-4-methylpentyl) - 1, 4 , 5, 8-tetramethoxynaphthalene was disεolved in 25ml of acetonitrile and then a εolution of 8.6g (17 mmole) of cerium (IV) ammonium nitrate diεεolved in 25ml of distilled water was added dropwiεe thereto over 30 minutes through a dropping funnel in a cooling bath (0-5°C) . The reaction mixture was stirred at normal temperature for 2 hours. After adding 60ml of distilled water thereto, the reaction mixture was extracted twice with dichloromethane solvent, dried over anhydrous magnesium sulfate and then filtered through filter paper. The resulting filtrate waε concen- trated under reduced pressure to obtain a crude product. The crude product waε purified by silica gel column chroma¬ tography (silica gel 4.0 X 15cm) using the solvent condi- tion which increases the amount of ethylacetate so that the n-hexane/ethylacetate ratio can vary from 10:1 to 1:1, to obtain 300mg of the title compound as a yellow precipitate. Yield : 27% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.10 ^-H-NMR (CDC1 3 , δ ppm) : 7.33(s, 2H) , 6.81(d, J=1.0Hz, IH) , 4.52(m, IH) , 3.96(ε, 6H) , 3.44(m, 2H) , 1.90-1.10 (m, 5H) , 1.20(t, J=7.1Hz, 3H) , 0.87(d, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 184.9, 184.8, 153.6, 153.3, 150.8, 133.1, 121.2, 121.0, 120.3, 119.9, 74.9, 64.9, 56.7, 56.6, 34.5, 33.9, 27.7, 22.4, 22.2, 15.1 IR : 2950, 1650, 1470, 1270 MASS : 346(M + , 31), 317(100), 302(14), 257(14) , 243 (11), 219(11), 149(5), 86(14), 84(18) EXAMPLE 40 : Preparation of 2-r1- (3-methylbutoxy) -4-methyl- pentyl1-5 , 8-dimethoxy-l , 4-naphthoquinone • According to the εame procedure aε Example 39, 2-[l- (4-methylbutoxy) -4-methylpentyl]-1, 4,5, 8-tetramethoxynapht- halene was used to obtain 476mg of the title compound as a reddish brown precipitate. Yield : 36% TLC (n-hexane:ethylacetate=2: 1) : Rf=0.21 Melting Point : 90.0-91.7°C 1 H-NMR (CDC1 3 , δ ppm) : 7.33(s, 2H) , 6.82(s, IH) , 4.51(m, IH) , 3.97(ε, 3H) , 3.42(m, 2H) , 1.90-1.10(m, 8H) , 0.89(d, J=6.3Hz, 6H) , 0.87(d, J=6.3Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 184.9, 184.6, 153.7, 153.3, 150.9, 133.2, 121.3, 121.1, 120.3, 119.9, 75.1, 68.1, 56.7, 56.6, 38.5, 34.5, 33.9, 27.7, 24.8, 22.5, 22.4, 22.3, 22.2 IR 2950, 1650, 1470, 1275 MASS : 338888 ((MM »+ + ,, 2200)) ,, 330033((1155)) ,, 247(3) , 203(6) , 131(3), 115(4) , 71(10), 55(15) , 43(100) EXAMPLE 41 : Preparation of 2- (l-pentyloxy-4-methylpentyl) - 5 ,8-dimethoxy-l,4-naphthoquinone According to the same procedure as Example 39, 2-(l- pentyloxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaphthalene was used to obtain 597mg of the title compound as a yellow precipitate. Yield : 46% TLC (n-hexane:ethylacetate=2: 1) : Rf=0.19 Melting Point * : 78.9-80.3°C 1 H-NMR (CDC1 3 , δ ppm) : 7.33(s, 2H) , 6.81(ε, IH) , 4.47(m, IH) , 3.96(s, 6H) , 3.34(m, 2H) , 1.80-1.15 (m, 11H) , 0.95-0.75(m, 9H) 184.9, 184.8, 153.6, 153.3, 150.8, 133.2, 121.2, 121.1, 120.3, 119.9, 75.1, 69.8, 56.7, 56.6, 34.5, 33.9, 29.3, 28.1, 27.7, 22.5, 22.2, 22.1, 13 IR : 2950, 2650, 1475 EXAMPLE 42 : Preparation of 2- (l-heptyloxy-4-methylpentyl) - 5 , 8-dimethoxy-l , 4-naphthoquinone According to the εame procedure aε Example 39, 2-(l- heptyloxy-4-methylpentyl] -1,4,5, 8-tetramethoxynaphthalene waε used to obtain 515mg of the title compound as a yellow¬ ish red oil. Yield : 37 % TLC (n-hexane:ethylacetate=2: 1) : Rf=0.15 1 H-NMR (CDC1 3 , δ ppm) : 7.34(s, 2H) , 6.83(s, IH) , 4.52(m, IH) , 5.98(ε, 6H) , 3.41(m, 2H) , 1.80-1.15(m, 15H) , 0.95-0.75(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 185.0(2C) , 153.7, 153.3, 150.9, 133.2, 121.3, 121.1, 120.3, 119.9, 75.1, 69.8, 56.7, 56.6, 34.6, 33.9, 31.6, 29.7, 28.9, 27.7, 25.9, 22.6, 22.4, 22.2, 13.9 IR : 2950, 1650, 1475 EXAMPLE 43 : Preparation of 2- (l-dodecyloxy-4-methylpentyl) -5.8-dimethoxy-l , 4-naphthoquinone According to the εame procedure as Example 39, 2-(l- dodecyloxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaphthalene was used to obtain 360mg of the title compound as a yellow¬ ish red oil. Yield : 54% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.22 1 H-NMR (CDC13, δ ppm) : 6.96(s, IH) , 6.82(s, 2H) , 4.83(m, IH) , 3.93(Ξ, 6H) , 3.89(s, 3H) , 3.75(s, 3H) , 3.30(t, J=6.3Hz, 2H) , 1.90-1.10(m, 25H) , 1.90-1.75 (m, 9H) 153.5, 151.5, 150.3, 147.3, 133.6, 124.0, 120.2, 108.4, 107.7, 105.7, 75.5, 69.1, 62.5, 57.9, 56.9(2C) , 35.8, 35.7, 35.3, 31.9, 29.9, 29.6, 29.4, 29.3, 28.0, 26.4, 22.6, 22.5, 14.0 IR : 2925, 1600, 1460, 1320 EXAMPLE 44 : Preparation of 2- (1-hvdroχypentyl) -5 ,8-dihvd- roxy-1 , 4-naphthoquinone 1.7g (5.6 mmole) of the compound prepared in Example 32 and 4.16g (33.5 mmole) of silver oxide (II) were dis- εolved in 30ml of acetone and then 40ml of 40% aqueouε HN0 3 εolution waε added dropwise thereto over 10 minutes through a dropping funnel in a cooling bath. The reaction mixture was εtirred at normal temperature for 3 hourε, extracted with dichloromethane, dried over anhydrouε magneεium εul- fate and then filtered through filter paper. The filtrate was concentrated under reduced presεure to obtain a crude product. The crude product waε purified by εilica gel column chromatography (silica gel 2.5 X 15cm) using the solvent condition which increases the amount of ethylace- tate so that the n-hexane/ethylacetate ratio can vary from 20:1 to 4:1, to obtain 540mg of the title compound aε a red precipitate. Yield : 35% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.29 Melting Point : 99.0-102.0°C ■ " ■ H-NMR (CDC1 3 , δ ppm) : 12.55(ε, IH) , 12.43(ε, IH) , 7.17(ε, 2H) , 7.11(d, J=1.0Hz, IH) , 4.90(m, IH) , 2.48(s, IH) , 1.75(m, 2H) , 1.60-1.15(m, 4H) , 0.92(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 180.2, 179.5, 165.9, 165.2, 152.0, 132.4, 32.1, 132.0, 112.0, 111.5, 68.9, 36.5, 27.7, 22.4, 13.9 IR : 2925, 1605, 1450, 1200 MASS 2 27766((MM ++ ,, 6 666)) , 2 27755((2244)) , 229(10) , 220(17) 219 (100) , 192(7) , 111(3) EXAMPLE 45 : Preparation of 2- (1-hydroxyhexyl) -5 , 8-dihydro- xy-1 , 4-naphthoquinone According to the same procedure as Example 44, the compound prepared in Example 33 was used to obtain 674mg of the title compound as a red precipitate. Yield : 40% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.30 Melting Point : 99.7-101.0°C 1 H-NMR (CDC1 3 , δ ppm) : 12.53(s, IH) , 12.41(s, IH) , 7.15(s, 2H) , 7.10(d, J=1.0Hz, IH) , 4.88(m, IH) , 2.69(br.s, IH) , 1.73 (m, 2H) , 1.55-1.10(m, 6H) , 0.89(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 180.1, 179.4, 165.8, 165.2, 152.1, 132.3, 132.0, 131.9, 111.9, 111.4, 68.7, 36.7, 31.5, 25.3, 22.5, 14.0 IR : 3450, 2925, 1600, 1450 MASS : 290(M + , 6) , 229(8) , 219(83) , 191(11) , 167(28) , 149(100) , 107(5) , 71(21), 57(28) EXAMPLE 46 : Preparation of 2- f1-hvdroχyoctyl) -5.8-dihvdro- xy-1,4-naphthoquinone According to the same procedure aε Example 44, the compound prepared in Example 34 waε uεed to obtain 716mg of the title compound as a red precipitate. Yield : 40% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.51 Melting Point : 62.5-63.7°C 1 H-NMR (CDC1 3 , δ ppm) : 12.54(s, IH) , 12.42(s, IH) , 7.16(s, 2H) , 7.10(d, J=0.9HZ, IH) , 4.88(m, IH) , 2.64(m, IH) , 1.71(m, 2H) , 1.70-1.10(m, 10H) , 0.87(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 180.2, 179.5, 165.8, 165.1, 152.1, 132.3, 132.1, 131.9, 112.0, 111.4, 68.7, 36.8, 31.7, 29.3, 29.1, 25.7, 22.6, 14.0 IR : 3450, 2925, 1600, 1450 MASS : 318(M + , 22) , 300(21) , 229(10) , 219(100) , 205 (11) , 137(3) , 97(5) , 83(6) EXAMPLE 47 Preparation of 2- (1-hydroxydecyl) -5.8-dihvdr- oxy-1 , 4-naphthoquinone According to the same procedure as Example 44, the compound prepared in Example 35 was used to obtain 1.05g of the title compound aε a red precipitate. Yield : 55% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.38 Melting Point : 74.1-75.2°C -•-H-NMR (CDC1 3 , δ ppm) : 12.57(ε, IH) , 12.45(s, IH) , 7.18(s, 2H) , 7.12(d, J=1.0Hz, ' IH) , 4.88(m, IH) , 2.41(br.ε, IH) , 1.70(m, 2H) , 1.60-1.00(m, 14H) , 0.87 (t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 180.3, 179.7, 165.8, 165.1, 152.0, 132.4, 132.2, 132.0, 112.0, 111.5, 68.9, 36.8, 31.8, 29.5, 29.3(2C) , 29.2, 25.7, 22.6, 14.1 IR : 3450, 2920, 1605, 1450 MASS : 346(M + , 29) , 328(16), 234(5) , 219(100), 205 (27) , 192(27) , 149(5) , 85(2) EXAMPLE 48 Preparation of 2-(1-hydroxytridecyl) -5.8-dihy- droxy-1 , 4-naphthoquinone According to the same procedure as Example 44, the compound prepared in Example 36 was used to obtain 0.73g of the title compound as a red precipitate. Yield 34! TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.41 Melting Point : 77.5-79.2°C ^-H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.44(s, IH) , 7.17(s, 2H) , 7.11(d, J=l.lHz, IH) , 4.85(m, IH) , 2.50(d, J=5.4Hz, IH) , 1.90-1.10(m, 22H) , 0.87(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 180.4, 179.6, 165.8, 165.2, 152.0, 132.4, 132.1, 112.0, 111.5, 68.9, 36.8, 31.9, 29.6, 29.5(6C), 25.7, 22.7, 14.1 IR : 2910, 1605, 1450, 1200 MASS : 388(M + , 34) , 370(23) , 220(29) , 219(100) , 205 (9) , 92(10) , 71(11) EXAMPLE 49 : Preparation of 2-(l-hydroxy-3-methylbut-2- enyl) -5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 44, the compound prepared in Example 37 was used to obtain the title compound as a yellow precipitate. Yield : 30% TLC (n-hexane:ethylacetate=2: 1) : Rf=0.25 Melting Point : 154.5-156.1°C ^-H-NMR (CDC1 3 , δ ppm) : 12.54(s, IH) , 12.10(s, IH) , 7.15(s, 2H) , 7.10- 6.50(m, 3H) , 1.43(s, 6H) IR : 2970, 1650, 1475 EXAMPLE 50 : Preparation of 2-fl-acetoxy-4-methylpentyl) - 5 , 8-dihvdroxy-l , 4-naphthoquinone According to the same procedure as Example 44, the compound prepared in Example 38 was used to obtain the title compound as a reddish brown precipitate. Yield : 45% TLC (n-hexane: ethylacetate=5: 1) : Rf=0.32 Melting Point : 105.0-106.8°C ^-H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.16(s, 2H) , 6.99(d, J=0.9Hz, IH) , 5.98(m, IH) , 2.14(s, 3H) , 2.00- 1.10(m, 5H) , 0.88(d, J=6.2Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 177.9, 176.4, 169.8, 167.8, 167.3, 132.9, 132.8, 131.0, 111.9, 111.6, 69.6, 34.3, 32.5, 27.7, 22.6, 22.2, 20.9 IR : 2950, 1740, 1610, 1450 EXAMPLE 51 : Preparation of 2-(l-ethoxy-4-methylpentyl) - 5 , 8-dihydroxy-l , 4-naphthoquinone 170mg (0.5 mmole) of the compound prepared in Example 39 and 310mg (2.5 mmole) of silver oxide (II) were dis- solved in 20ml of acetone and then 3.6ml of 40% aqueous HN0 3 solution was added dropwise thereto over 10 minutes through a dropping funnel in a cooling bath. The reaction mixture was stirred at normal temperature for 3 hours, extracted with dichloromethane, dried over anhydrous agne- sium sulfate and then filtered through filter paper. The filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was purified by silica gel column chromatography (silica gel 1.5 X 10cm) uεing the solvent condition which increases the amount of ethylace- tate so that the n-hexane/ethylacetate ratio can vary from 20:1 to 4:1, to obtain 48mg of the title compound aε a red precipitate. Yield : 30% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.54 Melting Point : 59.5-61.8°C ^-H-NMR (CDC1 3 , δ ppm) : 12.59(s, IH) , 12.50(s, IH) , 7.18(s, 2H) , 7.14(d, J=1.0Hz), 4.58(m, IH) , 3.46(q, J=7.3Hz, 2H) , 1.90-1.10(m, 8H) , 0.89(d, J=6.3Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 179.7, 179.0, 166.5, 166.0, 151.6, 132.5, 131.9, 112.1, 111.7, 75.1, 65.4, 34.6, 34.2, 27.9, 22.7, 22.4, 15.3 IR : 2950, 1600, 1450, 1340 MASS : 318(M + , 42) , 289(21), 274(22), 248(44) , 247 (100), 229(49) , 219(100) , 204(21), 149(12), 69(17) EXAMPLE 52 : Preparation of 2-f1-(3-methylbutoxy) -4-methyl- pentyl]-5.8-dihydroxy-l ,4-naphthoquinone According to the same procedure aε Example 51, the compound prepared in Example 40 was used to obtain 82.6mg of the title compound as a red precipitate. Yield : 46% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.53 Melting Point : 64.0-65.2°C ^-H-NMR (CDCl 3 , δ ppm) : 12.58(s, IH) , 12.49(s, IH) , 7.17-7.13 (m, 3H) , 4.59(m, IH) , 3.40(m, 2H) , 1.90-1.10 (m, 8H) , 0.89(d, J=6.0Hz, 12H) 13 C-NMR (CDC1 3 , δ ppm) : 179.8, 179.1, 166.3, 165.7, 151.6, 132.4, 132.0, 131.9, 112.0, 111.6, 75.2, 68.4, 38.7, 34.5, 34.0, 27.8, 25.0, 22.7, 22.6, 22.5, 22.3 IR : 2750, 1610, 1450, 1340 MASS : 336600((MM , + +,, 55)) ,, 228899((2211)) ,, 2219(54), 205(12) , 149(6) 137(7) , 99(11) , 97(30) , 71(76) , 43(100) EXAMPLE 53 : Preparation of 2- fl-pentyloxy-4-methylpentyl) - 5 , 8-dihydroxy-l , 4-naphthoquinone According to the εame procedure aε Example 51, the compound prepared in Example 41 waε used to obtain 62mg of the title compound as a red precipitate. Yield : 35% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.54 Melting Point : 68.5-69.8°C 1 H-NMR (CDC1 3 , δ ppm) :. 12.60(s, IH) , 12.50(ε, IH) , 7.18(s, IH) , 7.13(d, J=9.0Hz, IH) , 4.60(m, IH) , 3.36(m, 2H) , 1.80(m, 11H) , 0.95-0.75(m, 9H) 13 C-NMR (CDC13, δ ppm) : 179.8, 179.1, 166.3, 165.8, 151.6, 132.4, 132.1, 132.0, 112.1, 111.6, 75.5, 70.1, 34.5, 34.1, 29.5, 28.3, 27.8, 22.6, 22.4, 22.3, 14.0 IR : 2950, 1600, 1450 EXAMPLE 54 : Preparation of 2- (l-heptyloxy-4-methylpentyl) - 5 ,8-dihvdroxy-l,4-naphthoquinone According to the same procedure as Example 51, the compound prepared in Example 42 was used to obtain 119mg of the title compound as a red precipitate. Yield : 37% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.52 Melting Point : 40.2-42.7°C 1 H-NMR (CDC1 3 , δ ppm) : 12.60(s, IH) , 12.50(s, IH) , 7.18(s, 2H) , 7.13(d, J=0.9Hz, IH) , 4.56(m, IH) , 3.39(m, 2H) , 1.80- 1.10(m, 15H) , 0.95-0.75(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 179.8, 179.1, 166.4, 165.8, 151.7, 132.4, 132.1, 132.0, 112.1, 111.6, 75.2, 70.2, 34.6, 34.1, 31.8, 29.9, 29.1, 27.9, 26.1, 22.7, 22.6, 22.3, 14.0 IR : 2950, 1605, 1450 EXAMPLE 55 : Preparation of 2- (l-dodecyloxy-4-methylpentyl) -5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 51, the compound prepared in Example 43 was uεed to obtain 105mg of the title compound aε a red precipitate. Yield : 46% TLC (n-hexane: ethylacetate=5: 1) : Rf=0.57 Melting Point : 48.8-51.2°C 1 H-NMR (CDC1 3 , δ ppm) : 12.58(s, IH) , 12.48(s, IH) , 7.16(ε, 2H) , 7.13(d, J=0.9HZ, ' IH) , 4.56(m, IH) , 3.36(m, 2H) , 1.90- 1.00(m, 25H) , 0.95-0.70(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 179.8, 179.1, 166.3, 165.7, 151.7, 132.4, 132.0(C) , 112.1, 111.6, 75.2, 70.2, 34.6, 34.3, 34.1, 31.9, 29.9, 29.6, 29.4, 29.3, 27.9, 26.2, 21.9, 14.0, 22.6, 22.4, 22.3 IR : 2925, 1605, 1450, 1340 MASS : 458(M + , 15) , 387(70) , 274(37) , 229(14) , 219 (100) , 149(9) , 127(12) , 113(8) , 85(14) , 71(20) , 57(20) EXAMPLE 56 : Preparation of 2- (1-acetoxyhexyl) -5 , 8-dihydr- oxy-1 , 4-naphthoquinone In a 25ml two-neck flaεk 1 mmole of the compound prepared in Example 45, 266mg (1.1 mole) of DCC and 30mg (0.25 mmole) of 4-dimethylaminopyridine were introduced and then 3ml of dry dichloromethane waε added thereto. After adding 60mg (1 mmole) of acetic acid at 0°C under nitrogen gaε, the reaction mixture was stirred for 30 minutes and then subsequently stirred at normal temperature for further 3 hourε. To the reaction mixture was added 20ml of n- hexane. The mixture was stirred for further 10 minutes and then filtered to remove the insoluble materials. The filtrate was concentrated under reduced preεεure to obtain a crude product. The crude product waε purified by εilica gel column chromatography (silica gel 2.5 X 20cm) using the solvent condition which increases the amount of ethylace¬ tate so that the n-hexane/ethylacetate ratio can vary from 20:1 to 5:1, to obtain 256mg of the title compound as a reddish brown precipitate. Yield : 77% TLC (n-hexane:ethylacetate=2: 1) : Rf=0.39 Melting Point : 97.0-98.4°C 1 H-NMR (CDC1 3 , ' δ ppm) : 12.55(s, IH) , 12.40(ε, IH) , 7.17(ε, 2H) , 6.99(d, J=1.0HZ, IH) , 6.00(m, IH) , 2.15(ε, 3H) , 2.00- 1.20(m, 9H) , 0.82(t, J=6.3Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.1, 176.5, 169.8, 167.5, 167.0, 148.9, 132.9, 132.7, 131.0, 111.8, 111.5, 69.4, 34.5, 31.3, 25.0, 22.4, 20.9, 13.9 IR : 2950, 1740, 1610, 1455 EXAMPLE 57 : Preparation of 2- (1-hexanoyloxyhexyl) -5 , 8- dihydroxy-1 , 4-naphthoquinone According to the same procedure as Example 56, except that n-hexanoic acid is used inεtead of acetic acid used in Example 56, 258mg of the title compound was obtained as a reddish brown precipitate. Yield : 73% TLC (n-hexane: ethylacetate=5: 1) : Rf=0.43 1 H-NMR (CDC1 3 , δ ppm) : 12.55(ε, IH) , 12.39(s, IH) , 7.16(s, 2H) , 6.98(d, J=1.0HZ, IH) , 6.01(m, IH) , 2.41(t, J=7.3Hz, 2H) , 5 1.95-1.10(m, 14H) , 1.00-0.80(m, 6H) 178.2, 176.6, 172.6, 167.3, 166.8, 149.1, 132.7, 132.6, 131.0, 122.8, 111.5, 69.0, 34.5, 34.2, 31.2, 25.0, 24.6, 22.3, 22.2, 13.8, 13.7 Q IR : 2950, 1740, 1610, 1450 EXAMPLE 58 : Preparation of 2-(1-octanoyloxyhexyl) -5 , 8- dihydroxy-1 , 4-naphthoquinone 5 According to the εame procedure aε Example 56, except that n-octanoic acid iε uεed instead of acetic acid used in Example 56, 338mg of the title compound was obtained as a reddish brown precipitate. 0 Yield : 78% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.45 ^-H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.17(s, 2H) , 6.98(d, 5 J=1.0Hz, IH) , 6.01(m, IH) , 2.41(t, J=7.3Hz, 2H) , 1.95-1.10(m, 18H) , 1.00-0.80 (m, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 178.2, 176.6, 172.7, 167.5, 167.0, 149.2, 132.8, 132.7, 131.0, 111.9, 111.6, 69.1, 34.5, 34.3, 0 31.6, 31.3, 29.1, 28.9, 25.0, 24.9, 22.6, 22.4, 14.0, 13.9 IR : 2925, 1740, 1610, 1450 5 EXAMPLE 59 : Preparation of 2-[1-(3-tranε-hexenoyloxy) - hexyll-5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 56, except that 3-trans-hexenoic acid is used instead of acetic acid used in Example 56, 167mg of the title compound was ob¬ tained as a reddish brown precipitate. Yield : 43% TLC (n-hexane: ethylacetate=5 : 1) : Rf=0.45 ^-H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.17(s, 2H) , 6.97(d, J=0.9Hz, IH) , 6.00(m, IH) , 5.63(m, 2H) , 3.13(d, J=6.0Hz, 2H) , 2.25-0.85(m, 17H) 178.1, 176.6, 171.0, 167.6, 167.1, 149.0, 137.1, 132.9, 132.7, 131.1, 119.9, 111.9, 111.6, 69.4, 38.0, 34.5, 31.3, 25.5, 25.0, 22.4, 13.9, 13.4 IR : 2950, 1740, 1610, 1450 EXAMPLE 60 : Preparation of 2- (l-acetoxy-4-methylpentyl) - 5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 56, except that the known compound 2- ( l-hydroxy-4-methylpentyl) -5 , 8- dihydroxy-l, 4-naphthoquinone is used as the starting com- pound, 298mg of the title compound waε obtained aε a red¬ dish brown precipitate. Yield : 90% TLC (n-hexane: ethylacetate=5: 1) : Rf=0.32 Melting Point : 105.0-106.8°C 12.56(s, IH) , 12.41(s, IH) , 7.16(s, 2H) , 6.99(d, J=0.9Hz, IH) , 5.98(m, IH) , 2.14(ε, 3H) , 2.00- 1.10(m, 5H) , 0.88(d, J=6.2Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 177.9, 176.4, 169,8, 167.8, 167.3, 148.9, 132.9, 132.8, 131.0, 111.9, 111.6, 69.6, 34.3, 32.5, 27.7, 22.6, 22.2, 20.9 IR : 2950, 1740, 1610, 1450 EXAMPLE 61 : Preparation of 2-(l-hexanoyl-4-methylpentyl) - 5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 56, except that n-hexanoic acid is used instead of acetic acid used in Example 56, 349mg of the title compound was obtained as a reddish brown precipitate. Yield : 90% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.54 Melting Point : 60.7-62.3°C 1 H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.40(ε, IH) , 7.16(s, 2H) , 6.98(d, J=1.0Hz, IH) , 5.99(m, IH) , 2.41(t, J=1.0Hz, IH) , 5.99(m, IH) , 2.41(t, J=7.5Hz, 2H) , 2.00-1.10(m, 11H) , 0.95-0.75(m, 9H) 178.1, 176.6, 172.6, 167.5, 166.9, 149.1, 132.8, 132.6, 131.0, 111.8, 111.5, 69.2, 34.2, 32.5, 31.2, 27.7, 24.6, 22.6, 22.3, 22.2, 13.8 IR : 2950, 1740, 1610 EXAMPLE 62 : Preparation of 2- (l-octanoyloxy-4-methylpen- tyl) -5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 56, except that n-octanoic acid is used instead of acetic acid used in Example 56, 290mg of the title compound was obtained as a reddish brown precipitate. Yield : 70% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.55 Melting Point : 39.6-42.2°C 12.57(ε, IH) , 12.41(s, IH) , 7.17(s, 2H) , 6.98(d, J=0.9Hz, IH) , 5.99(m, IH) , 2.41(t, J=6.5Hz, 2H) , 2.00-1.10(m, 15H) , 0.95-0.75(m, 9H) 178.1, 176.6, 172.7, 167.6, 167.0, 149.2, 132.7, 132.6, 131.1, 111.9, 111.6, 69.3, 34.3, 32.5, 31.6, 29.1, 28.9, 27.7, 24.9, 22.6, 22.2, 22.1, 14.0 IR : 2950, 1740, 1605, 1450 EXAMPLE 63 : Preparation of 2-f1- (3-trans-hexenoyloxy) -4- methylpenty11-5 , 8-dihydroxy-l ,4-naphthoqui- none According to the same procedure aε Example 56, except that 3-tranε-hexenoic acid iε uεed inεtead of acetic acid used in Example 56, 292mg of the title compound was ob¬ tained as a reddish brown precipitate. Yield : 75% TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.50 ^-H-NMR (CDC1 3 , <S ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.17(s, 2H) , 6.98(d, J=1.0Hz, IH) , 5.98(m, IH) , 5.66(m, 2H) , 3.13(d, J=6.0Hz, 2H) , 2.25-1.20(m, 7H) , 1.01(t, J=7.3Hz, 3H) , 0.88(d, J=6.3Hz, 6H) 178.0, 176.4, 171.0, 167.6, 167.1, 148.9, 137.1, 132.9, 132.7, 131.0, 119.9, 111.8, 111.6, 69.5, 38.0, 34.2, 32.4, 27.7, 25.4, 22.6, 22.2, 13.3 IR : 2950, 1740, 1610, 1450 EXAMPLE 64 : Preparation of 2- (1-acetoxydecyl) -5 , 8-dihvdr- oxy-1 , 4-naphthoquinone According to the same procedure as Example 56, except that the compound prepared in Example 47 iε uεed aε the -- starting compound, 346mg of the title compound waε obtained as a reddish brown precipitate. Yield : .89% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.41 0 1 H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.40(s, IH) , 7.17(s, 2H) , 6.99(d, J=0.9Hz, IH) , 6.00(m, IH) , 2.15(s, 3H) , 1.95- 1.10(m, 16H) , 0.87(t, J=6.3Hz, 3H) 5 178.1, 176.5, 169.8, 167.5, 167.0, 148.9, 132.8, 132.6, 131.0, 131.0, 111.8, 111.5, 69.4, 34.5, 31.8, 29.4, 29.3(2C) , 29.1, 25.3, 22.6, 20.9, 14.0 IR : 2925, 1745, 1610, 1455 0 EXAMPLE 65 : Preparation of 2-(1-hexanoyloxydecyl) -5 ,8- dihydroxy-1 , 4-naphthoquinone 5 According to the same procedure as Example 64, except that n-hexanoic acid is uεed instead of acetic acid used in Example 64, 269mg of the title compound waε obtained as a reddish brown precipitate. 0 Yield : 61% TLC (n-hexane:e-thylacetate=5: 1) : Rf=0.57 12.56(s, IH) , 12.40(s, IH) , 7.17(s, 2H) , 6.98(d, J=1.0Hz, IH) , 6.00(m, IH) , 2.40(t, J=7.0Hz, 2H) , 1.85-1.10(m, 26H) , 1.00-0.75 (m, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 178.2, 176.6, 172.6, 167.5, 166.9, 149.2, 132.8, 132.6, 131.0, 111.8, 111.5, 69.1, 34.5, 34.2, 31.8, 31.2, 29.4, 29.3, 29.2, 29.1, 25.3, 24.6, 22.6, 22.3 , 14.0, 13.8 IR : 2950, 1740, 1605 EXAMPLE 66 : Preparation of 2-(1-octanoyloxydecyl) -5 ,8- dihvdroxy-1 ,4-naphthoquinone According to the same procedure as Example 64, except that n-octanoic acid iε used instead of acetic acid used in Example 64, 327mg of the title compound was obtained as a reddish brown precipitate. Yield : 69% TLC (n-hexane:ethylacetate=5: 1) Rf=0.60 Melting Point : 52.7-53.7°C 1 H-NMR (CDC1 3 , ' δ ppm) : 12.56(s, IH) , 12.40(s, IH) , 7.16(s, IH) , 6.98 (m, IH) , 2.41(t, J=7.0Hz, 2H) , 1.95-1.10(m, 26H) , 1.00-0.80(m, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.7, 172.6, 167.4, 166.9, 149.2, 132.8, 132.6, 131.1, 111.8, 111.6, 69.1, 34.6, 34.3, 31.8, 29.4, 29.3, 29.3, 29.2, 29.0, 28.9, 25.4, 24.9, 22.6, 22.5, 14.1, 14.0 IR : 2950, 1740, 1605, 1450 EXAMPLE 67 : Preparation of 2-f 1-π-trans-hexenoyloxy) - decyl]-5 , 8-dihydroxy-l , 4-naphthoquinone According to the same procedure as Example 64, except that 3-trans-hexenoic acid is used instead of acetic acid used in Example 64, 184mg of the title compound waε ob¬ tained aε a reddish brown precipitate. Yield : 42 % TLC (n-hexane:ethylacetate=4 : 1) : Rf=0.42 Melting Point : 95.3-97.3°C ^-H-NMR (CDC1 3 , δ ppm) : 12.56(s, IH) , 12.41(s, IH) , 7.17(s, 2H) , 6.97(d, J=1.0Hz, IH) , 5.99(m, IH) , 5.71(m, 2H) , 3.11(d, J=6.0Hz, 2H) , 2.25-0.80(m, 24H) 13 C-NMR (CDC1 3 , δ ppm) : 178.1, 176.6, 171.0, 167.5, 167.0, 148.9, 137.1, 132.9, 132.6, 131.0, 119.9, 111.8, 111.5, 69.4, 38.0, 34.5, 31.8, 29.7, 29.4, 29.3, 29.2, 29.1, 25.3, 22.6, 14.0, 13.3 IR : 2925, 1740, 1610, 1450 EXAMPLE 68 : Preparation of 2-(1-acetoxytridecyl) -5.8-dih- ydroxy-1 ,4-naphthoquinone According to the same procedure as Example 56, except that the compound prepared in Example 48 is uεed aε the starting compound, 387mg of the title compound was obtained as a reddish brown precipitate. Yield : 90% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.43 Melting Point : 87.5-88.5°C 1 H-NMR (CDC1 3 , δ ppm) : 12.55(Ξ, IH) , 12.39(s, IH) , 7.16(s, 2H) , 6.98(d, J=1.0Hz, IH) , 6.00(m, IH) , 2.15(s, 3H) , 1.95- 1.10(m, 22H) , 0.87(t, J=6.3Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.1, 176.6, 169.8, 167.4, 166.9, 148.9, 132.8, 132.6, 131.0, 111.8, 111.5, 69.4, 34.5, 31.9, 29.6, 29.5, 29.4, 29.3, 29.1, 25.3, 22.6, 20.9, 14.0 IR : 2925, 1740, 1610, 1450 EXAMPLE 69 : Preparation of 2-(1-butanoyloxytridecyl) -5, 8- dihydroxy-1 , 4-naphthoquinone According to the same procedure aε Example 68, except that n-butanoic acid iε uεed inεtead of acetic acid uεed in Example 68, 39lmg of the title compound waε obtained aε a reddish brown precipitate. Yield : 85% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.50 Melting Point : 61.0-62.0°C ^ ■ H-NMR (CDC1 3 , <5 ppm) : 12.56(s, IH) , 12.40(s, IH) , 7.17(s, IH) , 6.97(d, J=0.9Hz, IH) , 6.00(m, IH) , 2.39(t, J=7.3Hz, 2H) , 1.90-1.10(m, 24H) , 0.98(t, J=6.3Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.7, 172.4, 167.5, 166.9, 149.2, 132.8, 132.6, 131.0, 111.8, 111.6, 69.1, 36.2, 34.6, 31.9, 29.6, 29.5(4C) , 29.3, 29.1, 25.4, 22.6, 18.4, 14.0, 13.6 IR : 2925, 1740, 1610, 1450 EXAMPLE 70 : Preparation of 2- (l-hexanoyloxytridecyl) -5 , 8- dihvdroxy-1 , 4-naphthoquinone According to the same procedure aε Example 68, except that n-hexanoic acid is used inεtead of acetic acid used in Example 68, 348mg of the title compound was obtained as a reddish brown precipitate. Yield : 71% TLC (n-hexane:ethylacetate=5: 1) : Rf=0.54 -"-H-NMR (CDC1 3 , δ ppm) : 12.55(s, IH) , 12.39(s, IH) , 7.16(s, 2H) , 6.97(d, J=0.9Hz, IH) , 6.00(m, IH) , 2.41(t, J=7.3Hz, 2H) , 1.95-1.10(m, 28H) , 1.00-0.75(m, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 178.3, 176.7, 172.6, 167.4, 166.8, 149.2, 132.7, 132.6, 131.0, 111.8, 111.5, 69.1, 34.5, 34.2, 31.9, 31.2, 29.6(3C) , 29.5, 29.4, 29.3, 29.1, 25.3, 24.6, 22.6, 22.3, 14.0, 13.8 IR : 2925, 1740, 1610, 1450 Preparation of the compound of formula (II) EXAMPLE 71 : Preparation of 2-(1-hydroxypentyl) -1.4 , 5, 8- tetramethoxynaphthalene 0.8g (33 mmole) of magnesium and 4.47g (33 mmole) of 1-bromobutane were added to 30ml of dry tetrahydrofuran and the mixture was stirred for 2 hours to obtain a Grignard reagent. A εolution of 3g (10.9 mmole) of 2-formyl- 1, 4 , 5, 8-tetramethoxynaphthalene diεεolved in 30ml of dry tetrahydrofuran was added dropwise to the Grignard reagent over 20 minutes through a dropping funnel. The reaction mixture was stirred at normal temperature for further one hour and then 80ml of 10% aqueouε ammonium chloride solu¬ tion was added thereto. The mixture waε extracted twice with dichloromethane εolvent, dried over anhydrous magnesi- urn εulfate and filtered through a filter paper. The filtrate was concentrated under reduced pressure. The residue waε purified by silica gel column chromatography (silica gel 4.0 X 20cm) using the solvent condition which increaseε the amount of ethylacetate so that the n- hexane/ethylacetate ratio can vary from 10:1 to 1:1, to obtain 3.08g of the title compound as a yellow precipitate. Yield : 85% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.23 ^-H-NMR (CDC1 3 , δ ppm) : 6.97(s, IH) , 6.80(ε, 2H) , 5.20(m, IH) , 3.88(ε, 6H) , 3.82(ε, 3H) , 3.72(s, 3H) , 2.60(d, J=3.5Hz, IH) , 1.76(m, 2H) , 1.55-1.20 (m, 4H) , 0.88(t, J=6.1Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 153.3, 151.3, 150.2, 146.3, 134.6, 122.5, 120.1, 108.2, 107.6, 105.8, 107.6, 105.8, 68.5, 62.7, 57.7, 57.0, 56.8, 38.0, 28.3, 22.6, 14.0 IR : 3450, 2950, 1600, 1360 MASS : 334(M + , 100) , 316(90) , 301(27) , 277(60) , 262 (50) , 235(18) , 220(15) , 84(68) , 57(3) EXAMPLE 72 : Preparation of 2- (1-hydroxyhexyl) -1 , 4 , 5 , 8- tetramethoxynaphthalene According to the same procedure as Example 71, except that l-bromopentane is used instead of 1-bromobutane used in Example 71, 3. Ig of the title compound was obtained as a pale yellow precipitate. Yield : 82% TLC (n-hexane: ethylacetate=l: 1) : Rf=0.42 Melting Point : 90.8-92.0°C 6.97(s, IH) , 6.80(s, 2H) , 5.24(m, IH) , 3.88(ε, 6H) , 3.84(ε, 3H) , 3.73(ε, 3H) , 2.55(d, J=3.5Hz, IH) , 1.76(m, 2H) , 1.50-1.15 (m, 4H) , 0.87(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 153.3, 151.3, 150.2, 146.3, 134.6, 122.5, 120.1, 108.1, 107.6, 105.8, 68.6, 62.7, 57.7, 57.0, 56.8, 38.3, 31.7, 25.8, 22.5, 14.0 IR : 3470, 2925, 1600, 1360 MASS : 348(M + , 100) , 277(58) , 262(28) , 234(21) , 99 (32) , 84(18) EXAMPLE 73 : Preparation of 2- ( l-hydroxyoctyll -1 , 4 , 5 , 8- tetra ethoxynaphthalene According to the same procedure as Example 71, except that 1-bromoheptane is used instead of 1-bromobutane used in Example 71, 3.3g of the title compound was obtained as a yellow precipitate. Yield : 81% TLC (n-hexane: ethylacetate=2: 1) : Rf=0.24 Melting Point : 69.7-7l.2°C ^ • H-NMR (CDC1 3 , δ ppm) : 6.97(s, IH) , 6.79(ε, 2H) , 5.21(m, IH) , 3.91(ε, 6H) , 3.87(s, 3H) , 3.72(s, 3H) , 2.61(d, J=3.0Hz, IH) , 1.75(m, 2H) , 1.50-1.15 (m, 10H) , 0.86(t, J=6.0Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 153.3, 151.3, 150.2, 146.3, 134.6, 122.5, 120.1, 108.2, 107.6, 105.9, 68.5, 62.7, 57.7, 57.0 IR : 3460, 2925, 1600, 1460 MASS : 376(M + , 65) , 367(20) , 358(96) , 344(100) , 329 (19) , 277(17) , 246(54), 231(29) , 187(6), 155(5) , 127(6) , 115(8) , 91(7) , 57(21) EXAMPLE 74 : Preparation of 2-(1-hvdroχydecyl) -1 ,4 , 5,8- tetramethoxynaphthalene According to the same procedure as Example 71, except that l-bromononane is used instead of l-bromobutane used in Example 71, 3.78g of the title compound was obtained aε a pale yellow precipitate. Yield : 85% TLC (n-hexane:ethylacetate=l: 1) : Rf=0.51 Melting Point : 63.0-64.4°C 6.98(s, IH) , 6.80(s, 2H) , 5.24(m, IH) , 3.92(ε, 6H) , 3.88(s, 3H) , 3.73(s, 3H) , 2.54(d, J=3.4Hz, IH) , 1.76(m, 2H) , 1.55-1.10(m, 14H) , 0.87(t, J=6.3Hz, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 153.3, 151.3, 150.2, 146.3, 134.6, 122.5, 120.1, 108.2, 107.6, 105.9, 68.6, 62.7, 57.7, 57.0, 56.8, 38.3, 31.8, 29.5(3C) , 29.2, 26.1, 22.6, 14.0 IR : 3470, 2925, 1600, 1360 MASS : 404(M + , 100) , 361(3) , 277(77) , 263(43) , 235 (17) , 234(16) , 220(26) , 155(9) , 85(18) EXAMPLE 75 : Preparation of 2- (1-hydroxytridecyl) -1 , 4 , 5 , 8- tetramethoxynaphthalene According to the same procedure as Example 71, except that 1-bromododecane is used instead of 1-bromobutane uεed in Example 71, 3.55g of the title compound was obtained as a pale yellow precipitate. Yield : 70% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.30 Melting Point : 69.0-73.0°C 1 H-NMR (CDC1 3 , δ ppm) : 6.97(s, IH) , 6.81(s, 2H) , 5.20(br.ε, IH) , 3.89(ε, 3H) , 3.74(m, 3H) , 2.42(ε, IH) , 1.76(m, 2H) , 1.50- 1.00(m, 20H) , 0.87 (m, 3H) 13 C-NMR (CDC1 3 , δ ppm) : 153.4, 151.4, 150.2, 146.4, 134.6, 122.5, 120.1, 108.2, 107.6, 105.8, 62.8, 57.7, 57.0, 56.8, 38.3, 31.9, 29.9, 29.6, 29.3, 28.9, 28.8, 26.2, 22.6, 14.0 IR 3440, 2920, 1600, 1460 MASS : 444466((MM ,+ + ,, 110000)) ,, 442288((9988)) ,, 413(16) , 277(37) , 262 (19) , 233(5) , 220(4) , 57(2) EXAMPLE 76 : Preparation of 2- (l-acetoxy-4-methylpentyl) - 1,4,5, 8-tetramethoxynaphthalene In a 25ml two-neck flaεk 1 mmole of 2- (l-hydroxy-4- methylpentyl) -1, 4 , 5, 8-tetramethoxynaphthalene, 226mg (1.1 mmole) of DCC and 30mg (0.25 mmole) of 4-dimethylaminopyri- dine were introduced and then 3ml of dry dichloromethane was added thereto. After adding 1 mmole of acetic acid at 0°C under nitrogen gas, the reaction mixture was stirred for 30 minutes and then εubεequently εtirred at normal temperature for further 3 hourε. To the reaction mixture waε added 20ml of n-hexane. The mixture was εtirred for further 10 minuteε and then filtered to remove the inεolu- ble materialε. The filtrate waε dried over anhydrouε magnesium εulfate to obtain a crude product. The crude product waε purified by εilica gel column chromatography (silica gel 2.5 X 20cm) using the solvent condition which increases the am unt of ethylacetate so that the n- hexane/ethylacetate ratio can vary from 20:1 to 5:1, to obtain the title compound as a pale yellow oil. Yield : 90% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.59 ^-H-NMR (CDC1 3 , <S ppm) : 6.86(s, IH) , 6.83(s, 2H) , 6.33(t, J=6.3Hz, IH) , 3.93(s, 6H) , 3.89(ε, 3H) , 3.84(ε, 3H) , 2.11(s, 3H) , 2.00-1.10(m, 5H) , 0.85(d, J=6.3Hz, 6H) 170.3, 153.4, 151.3, 150.5, 146.8, 131.1, 122.6, 120.6, 108.7, 107.7, 105.9, 71.2, 62.4, 57.9, 57.3, 56.9, 34.6, 34.0, 27.9, 22.5, 22.4, 21.2 IR : 2950, 1735, 1600, 1360 EXAMPLE 77 : Preparation of 2- (l-ethoxy-4-methylpentyl) - 1,4,5, 8-tetramethoxynaphthalene 850mg (2.44 mmole) of 2- (l-hydroxy-4-methylpentyl) - 1, 4 , 5, 8-tetramethoxynaphthalene and 510mg (12.2 mmole) of sodium hydride (55% dispersion in oil) were dissolved in 10ml of dry tetrahydrofuran and 1.9g (12.2 mmole) of iodo- ethane was added thereto under nitrogen gaε and then the mixture waε refluxed for 3 hourε. After adding 20ml of ice water, the reaction mixture was extracted twice with di¬ chloromethane, dried over anhydrous magnesium εulfate and filtered through a filter paper. The filtrate waε concen- trated under reduced preεsure to obtain a crude product. The crude product was purified by silica gel column chroma¬ tography (silica gel 2.5 X 15cm) using the εolvent condi¬ tion which increaεeε the amount of ethylacetate εo that the n-hexane/ethylacetate ratio can vary from 10:1 to 1:1, to obtain 780mg of the title compound aε a pale yellow oil. Yield : 85% TLC (n-hexane:ethylacetate=2 : 1) : Rf=0.50 ^-H-NMR (CDC1 3 , δ ppm) : 6.98(ε, IH) , 6.82(s, 2H) , 4.86(m, IH) , 3.94(s, 6H) , 3.89(s, 3H) , 3.76(s, 3H) , 3.38(q, J=7.0Hz, 3H) , 1.90-1.30(m, 5H) , 1.19(t, J=7.0Hz, 3H) , 0.87(d, J=5.0Hz, 6H) 13 C-NMR (CDC1 3 , δ ppm) : 153.5, 151.5, 150.2, 147.3, 133.4, 122.5, 120.2, 108.3, 107.6, 105.5, 75.5, 64.1, 62.5, 57.8, 56.9, 56.8, 35.7, 35.3, 28.0, 22.6, 22.5, 15.4 IR : 2950, 1600, 1450, 1360 MASS : 376(M + , 12), 305(17) , 276(6) , 231(3) , 86(100) , 84(100) EXAMPLE 78 : Preparation of 2-r1- (4-methylbutoxy') -4-methyl- penty11-1,4,5, 8-tetramethoxynaphthalene According to the same procedure aε Example 77, except that iodo-4-methylbutane is used instead of iodoethane used in Example 77, 729mg of the title compound was obtained as a yellow oil. Yield : 72% TLC (n-hexane: ethylacetate=2 : 1) : Rf=0.61 1 H-NMR (CDC1 3 , δ ppm) : 6.96(ε, IH) , 6.82(s, 2H) , 4.83 (m, IH) , 3.93(ε, 6H) , 3.90(s, 3H) , 3.75(s, 3H) , 3.33(t, J=6.3Hz, 2H) , 1.90-1.10(m, 8H) , 0.87(d, J=6.3Hz, 6H) , 0.83(d, J=6.3Hz, 6H) 13 C-NMR (CDC1 3 , <S ppm) : 153.6, 151.5, 150.3, 147.3, 133.6, 122.6, 120.2, 108.3, 107.6, 105.7, 75.8, 67.4, 62.6, 57.8, 57.0(2C) , 38.9, 35.9, 35.3, 28.0, 25.1, 22.7, . 22.6(2C) , 22.5 IR : 2950, 1600, 1460, 1360 MASS : 418(M + , 1) , 307(3) , 263(6) , 237(11) , 149(3) , 115(3)-, 91(6) , 71(3) , 55(24) , 43(100) EXAMPLE 79 : Preparation of 2- (l-pentyloxy-4-methylpentyl) - 1,4,5, 8-tetramethoxynaphthalene According to the same procedure as Example 77, except that iodo-n-pentane is used inεtead of iodoethane used in Example 77, 850mg of the title compound was obtained as a yellow oil. Yield : 83% TLC (n-hexane : ethylacetate=2 : 1) : Rf=0.60 1 H-NMR (CDC1 3 , δ ppm) : 6.97(s, IH) , 6.82(s, 2H) , 4.83(m, IH) , 3.94(s, 6H) , 3.75(ε, 3H) , 3.30(t, J=6.3Hz, 2H) , 1.85- 1.10(m, 11H) , 0.95-0.85(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 153.5, 151.5, 150.3, 147.3, 133.5, 122.5, 120.2, 108.3, 107.6, 105.6, 75.6, 69.0, 62.6, 57.8, 56.9(2C) , 35.8, 35.3, 29.6, 28.5, 28.0, 22.6, 22.5, 22.4, 14.0 IR : 2950, 1600, 1460, 1360 EXAMPLE 80 : Preparation of 2- (l-heptyloxy-4-methylpentyl) - 1,4,5, 8-tetramethoxynaphthalene According to the εame procedure as Example 77, except that iodo-n-heptane is used inεtead of iodoethane uεed in Example 77, 786mg of the title compound waε obtained as a yellow oil. Yield : 72% TLC (n-hexane: ethylacetate=2 : 1) : Rf=0.62 1 H-NMR (CDC1 3 , δ ppm) : 6.98(s, IH) , 6.82(s, 2H) , 4.84(m, IH) , 3.94(ε, 6H) , 3.76(s, 3H) , 3.31(t, J=6.3Hz, 2H) , 1.90- 1.10(m, 15H) , 0.95-0.75(m, 9H) 13 C-NMR (CDC1 3 , δ ppm) : 153.5, 151.5, 150.2, 147.2, 133.5, 122.5, 120.2, 108.3, 107.6, 105.6, 75.6, 69.0, 62.5, 57.8, 56.9(2C) , 35.8, 35.3, 31.8, 30.0, 29.6, 29.3, 28.3, 26.3, 22.6, 22.5, 22.4, 14.0 IR : 2950, 1600, 1460, 1360 EXAMPLE 81 : Preparation of 2- (l-dodecyloxy-4-methylpentyl) -1,4,5, 8-tetramethoxynaphthalene According to the εame procedure as Example 77, except that iodo-n-dodecane is used instead of iodoethane used in Example 77, 956mg of the title compound waε obtained aε a pale yellow oil. Yield : 76% TLC (n-hexane: ethylacetate=2 : 1) : Rf=0.39 6.96(s, IH) , 6.82(s, 2H) , 4.83 (m, IH) , 3.93(s, 6H) , 3.89(s, 3H) , 3.75(s, 3H) , 3.30(t, J=6.3Hz, 2H) , 1.90-1.10(m, 25H) , 1.90-1.75 (m, 9H) 153.5, 151.5, 150.3, 147.3, 133.6, 124.0, 120.2, 108.4, 107.7, 105.7, 75.5, 69.1, 62.5, 57.9, 56.9(2C) , 35.8, 35.7, 35.3, 31.9, 29.9, 29.6, 29.4, 29.3, 28.0, 26.4, 22.6, 22.5, 14.0 IR : 2925, 1600, 1460, 1320 TEST 1 : Experiment on cytotoxic activity A. Cytotoxic activity against L1210 cells To obtain L1210 cells in a logarithmic phase for cytotoxic activity test, in a 250ml Erlenmeyer flaεk with a εcrew cap, including Fiεher medium warmed to 36 to 37°C, L1210 cellε were adjusted to a concentration of 2-3X10 J cells/ml and then cultured, before 24 hourε from the begin¬ ning of experiment. Then, the culture solution thus obtained was εuspended to prepare a L1210 cell suεpenεion having a concentration of about 0.8-1.0X10 6 cellε/ l. Teεt εample was diεsoved in ethanol or dimethylsulfoxide in a certain concentration just before the experiment. 0.1ml of the sample εolution was diluted 10 times with 0.9ml of a fresh medium. To each screw-capped test tube were added 100, 50, 25μl, respectively, of the εample dilutionε and then added 5ml of the cell εuεpenεion (5X10 4 cells/ml) prepared above to use as the test group. To the test tubes for the control group ( 2VTT : n=number of the samples) , only 5ml of the cell suspension waε added. All test tubes were cultured for 48 hours in a C0 2 incubator at 37°C and then the number of cells was counted using a hae acytometer. B. Cytotoxic activity against HL-60 and K-562 cells As in the test for the cytotoxic activity against L1210 cells, the test samples were dissoved in ethanol or dimethylsulfoxide in a certain concentration. 0.1ml of the εample εolution waε mixed with 0.9ml of a freεh medium to prepare the dilutionε. To each two teεt tubes having a screw cap were added 100, 50, 25/il, respectively, of the sample dilutions by meanε of a micropipet. To each teεt tube for the teεt group and the control group (2VTT : n=number of the samples) was added 5ml of the dilutions of HL-60 cells and K-562 cells which were cultured and acti¬ vated before 24 hours from the beginning of experiment and then diluted in a concentration of 1X10 5 cells/ml. All teεt tubes were cultured for 48 hours in a C0 2 incubator at 37°C and then the number of cells was counted using a haemacytometer. The ED 50 value is defined aε a concentration (μg/ml) of the εample which inhibitε the growth of cancer cells by 50% of the control group and determined according to a method described in NIC'ε mannual (NIC=National Cancer Inεtitue, USA) . The growth rate Y(%) of cells in the presence of the teεt εample in each concentration waε calculated according to the followign equation : Y(%) = [(T-C 0 ) / (C-C 0 )] X 100 In the above equation, T means the average cell number per ml in the test group after incubation for 48 hours in the presence of the test samples in each concentration, C means the average cell number per ml in the control group after incubation for 48 hours, and C means the average cell number per ml in the control group at the beginning of incubation. The Y(%) value at each concentration and log 1Q value of each concentration were obtained and the regreεεion curve was constructed according to the following equation from those obtained values. In this case, when all the Y(%) value obtained at each concentration iε greater than 55% or lower than 45%, the experiment waε repeatedly conducted. To construct the regression curve Y=A+BX the values A and B were obtained using the following equation. N-∑(Xi-Yi) - (∑xi) • (ΣYi) B = Slope = N-Σ(Xi) 2 - (ΣXi) 2 ΣYi ΣXi A = Intercept = - B N N In the above, ' the value N is the number of selected pointε which is greater than 2 and lower than, or identical with, the number of cencentration of the teεt sample, Xi is log(concentration) i, and Yi is the growth ratio at (concen¬ tration)!. The value of ED 50 was obtained for those ob¬ tained slope and intercept. C. Cytotoxic activity against A549 cancer cells The cytotoxic activity against A549 cancer cells waε determined using a method for measuring εulforhodamin B (SRB) , which waε developed in the year 1989 by NIC for measuring anticancer activity of the drug in vitro. For the ' experiment, cells under subculturing were separated from the attached surface with trypsin-CDTA solution and then dispensed into a 24-well flat-bottom microplate (Falcon) so that the number of cells per well is 8X10 4 (A549) . The microplate was incubated in a C0 2 incubator for 24 hours to attach the dispensed cells to bottom. The medium was removed with aspirator. Then, lOOμl of the εolution of the test compounds diluted in a log-dose of 6 kinds of concentration was added to each well containing cells, in a multiple of 3. The microplate was incubated for further 48 hours. In addition, the diluted solution of the test compounds above was filtered through a 0.22μm filter, before addition to the cells, to keep the experi¬ ment under sterilized condition. The cells were incubated with the teεt compoundε for 48 hourε and then the medium waε removed from each well. lOOμl of 10% trichloroacetic acid (TCA) was added to each well and then the plate was allowed to stand at 4°C for one hour to fix the cells to the bottom of plate. After fixing the cells, the plate waε washed 5 to 6 times with water to completely remove any remaining TCA solution and then dried at room temperature until water is no longer present. To the completely dried plate was added the dying solution of 0.4% SRB dissolved in 1% acetic acid in an amount of 250μl per well to stain the cells for 30 minutes and then the plate was washed again 5 to 6 times with 1% acetic acid solution to remove the remaining SRB which is not bound to the cells. The stained cell plate was dried again at room temperature. Then, the dying solution was carefully disεolved in a certain amount of lOmM Triε εo that the O.D. value in the control group at 520nm is 0.8-l.θA (optical density) , and the optical density at 520nm waε determined. The ED 5Q value waε obtained from the determined optical denεity. To calculate the activity of the drug against cancer cells, the number of cells (Tz) at the beginning of the addition of drug, the number of cells (C) after incubation with the medium in the absence of drug for 48 hours and the number of cells (T) after incubation in the presence of drugs at each concentration for 48 hours were determined. The anticancer activity of the test compoundε was determined form the following equations. Specifically, in the case of Tz≥T the equation (T-Tz) / (C-Tz) X100 was uεed and in the case of Tz<T the equation (T-Tz) /TzXIOO was used. Then the IC 5Q value wich is the concentration of drug which inhibits the growth of cancer cellε by 50% waε calcualted from the above calculated values using a data regressive function of LOTUS programme and the cytotoxic activities of the test compounds were compared with each other. The results are liεted in the following Table 1, Table 1 Cytotoxic activity of the compound of the present invention aqainst cancer cells ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-(l-acetyloxy-4-methyl-3- pentenyl)-5,8-dihydroxy- <0.01 0.06 1.0 1,4-naphthoquinone 2-(1-monochloroacetyloxy- 4-methyl-3-pentenyl)-5,8- 0.12 0.3 4.0 dihydroxy-1,4-naphthoquinone 2-(l-trichloroacetylox ' y-4- methyl-3-pentenyl)-5,8- 0.01 0.3 2.0 di ydroxy-1, 4-naphthoquinone 2-(l-n-propionyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.03 0.04 1.9 1,4-naphthoquinone 2-(l-n-butanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.01 0.1 2.5 1,4-naphthoquinone 2-(l-isobutanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.003 0.2 1.9 1,4-naphthoquinone 2-(l-n-hexanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.2 0.7 2.6 1,4-naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-[ 1-(4-pentenoyl)oxy-4-methyl- 3-pentenyl]-5,8-dihydroxy- 0.02 0.5 1.0 1,4-naphthoquinone 2-[1-(3,3-dimethyl)acryloxy-4- methyl-3-pentenyl]-5,8- <0.01 0.05 1.1 dihydroxy-1,4-naρhthoquinone 2-(l-phenylacetyloxy-4 ' -methyl- 3-pentenyl)-5,8-dihydrσxy- 0.1 0.4 1.1 1,4-naphthoquinone 2-[1-(trans-2-hexenoyl)oxy-4- methyl-3-pentenyl]-5,8- 0.5 1.0 1.6 dihydroxy-1,4-naphthoquinone 2-[l-(trans-3-hexenoyl)oxy-4- methyl-3-pentenyl]-5,8- 0.3 0.9 3.3 dihydroxy-1,4-napht oquinone 2-[l-(6-heptenoyl)oxy-4-methyl- 3-pentenyl]-5, 8-dihydroxy- 0.2 0.5 4.2 1,4-naphthoquinone 2-(l-n-octanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.2 0.7 4.3 1,4-naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-(l-n-nonanoyloxy-4-methyl- 3-pentenyl ]-5,8-dihydroxy- 0.5 1.0 6.9 1,4-naphthoquinone 2-(l-n-decanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.7 1.1 15 1,4-naphthoquinone 2-(l-lauryloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.7 1.0 >20 1,4-naphthoquinone 2-(l-diphenylacetyloxy-4- methyl-3-pentenyl)-5,8- 0.2 0.4 6.3 dihydroxy-1,4-naphthoquinone 2-(l-undecylenoyloxy-4- methyl-3-pentenyl)-5,8- 0.01 0.3 6.7 dihydroxy-1,4-naphthoquinone 2-(l-stearyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 1.1 10 >20 1,4-naphthoquinone 2-(l-palmityloxy-4-methyl- 3-pentenyl)-5, 8-dihydroxy- 2.1 3.0 >20 1, 4-naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-(l-oleyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 2.4 9.6 >20 1,4-naphthoquinone 2-(l-linolenyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 1.5 4.8 >20 1,4-naphthoquinone 2-[1-(trans-retinoyl)o ' xy-4- methyl-3-pentenyl]-5,8- 3.1 4.3 >20 dihydroxy-1,4-naphthoquinone 2-[l-(cis-retinoyl)oxy-4- methyl-3-pentenyl)-5,8- 7.1 6.6 >20 dihydroxy-1, 4-naphthoquinone 2-(l-pentanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.2 0.6 2.5 1,4-naphthoquinone 2-[1-(trans-2-pentenoyloxy)-4- methyl-3-pentenyl ]-5, 8- 0.4 0.9 1.1 dihydroxy-1,4-naphthoquinone 2-[l-(2,4-hexadienoyloxy)-4- methyl-3-pentenyl]-5, 8- 0.5 0.6 0.7 dihydroxy-1, -naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 H -60 K562 A549 2-[l-(2, 6-heptadienoyloxy)-4- methyl-3-pentenyl]-5,8- 1.3 0.9 3.8 dihydroxy-1,4-naphthoquinone 2-(l-benzoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 0.1 0.1 2.1 1,4-naphthoquinone 2-[1-(9, 12-octadecenoy'loxy)- 4-methyl-3-pentenyl]-5,8- 5.0 12.5 >20 dihydroxy-1,4-naphthoquinone 2-(1-hydroxypentyl)-5,8- dimethoxy-1, -naphthoquinone 0.1 1.1 6.4 2-(1-hydroxyhexyl)-5,8- dimethoxy-1,4-naρhthoquinone 0.3 0.6 0.9 2-(l-hydroxy-4-methylpentyl)- 5,8-dimethoxy-l,4- 0.02 0.9 2.2 naphthoquinone 2-(1-hydroxyoctyl)-5, 8- dimethoxy-1,4-naphthoquinone 1.0 2.1 7.5 2-(1-hydroxydecyl)-5,8- dimethoxy-1,4-naphthoquinone 1.4 1.6 9.2 Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 H -60 K562 A549 2-(1-hydroxytridecyl)-5,8- dimethoxy-1,4-naphthoquinone 1.8 2.3 2.8 2-(1-hydroxypentyl)-5,8- dihydroxy-1, -naphthoquinone 0.04 0.08 0.5 2-(1-hydroxyhexy1)-5,8- dihydroxy-1,4-naphthoquinone 0.03 0.02 1.1 2-(l-hydroxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 0.05 0.01 0.9 naphthoquinone 2-(1-hydroxyoctyl)-5,8- dihydroxy-1,4-naphthoquinone 0.07 0.2 0.4 2-(1-hydroxydecyl)-5,8- dihydroxy-1, 4-naphthoquinone 0.1 0.3 0.5 2-(1-hydroxytridecyl)-5,8- dihydroxy-1,4-naphthoquinone 0.3 0.4 4.4 2-(1-acetoxyhexyl)-5,8- dihydroxy-1,4-naphthoquinone 0.08 0.01 0.7 2-( 1-hexenoyloxyhexyl)-5,8- dihydroxy-1, -naphthoquinone 0.1 0.2 0.3 Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-(1-octanoyloxyhexyl)-5,8- dihydroxy-1, 4-naphthoquinone 0.2 0.3 2.1 2-[1-(trans-3-hexenoyloxy)- hexyl]-5, 8-dihydroxy- 0.2 0.2 1.5 1,4-naphthoquinone 2-(l-acetoxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 0.05 0.07 1.5 naphthoquinone 2-(l-hexanoyloxy-4-methyl- pentyl)-5,8-dihydroxy- 0.3 0.05 0.4 1,4-naphthoquinone 2-( l-octanoyloxy-4-methyl- pentyl)-5, 8-dihydroxy- 0.5 0.6 1.7 1,4-naphthoquinone 2-[1-(trans-3-hexenoyloxy)- 4-methylpentyl]-5, 8-dihydroxy- 0.05 0.2 2.4 1,4-naphthoquinone 2-(1-acetoxydecyl)-5, 8- dihydroxy-1, -naphthoquinone 0.4 0.1 0.3 Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-(hexanoyloxydecyl)-5,8- dihydroxy-1,4-naphthoquinone 0.5 1.1 13.0 2-(1-octanoyloxydecyl)-5,8- dihydroxy-1,4-naphthoquinone 0.9 >20 >20 2-[l-(trans-3-hexenoyloxy)- decyl]-5,8-dihydroxy- 0.6 0.6 7.1 1,4-naphthoquinone 2-(1-acetoxytridecyl)-5,8- dihydroxy-1,4-naphthoquinone 0.4 4.2 15.8 2-(1-butanoyloxytridecyl)- 5,8-dihydroxy-l,4- 0.6 2.7 >20 naphthoquinone 2-(1-hexanoyloxytridecyl)- 5,8-dihydroxy-l,4- 1.5 >20 >20 naphthoquinone 2-(l-methoxy-4-methylpentyl)- 5,8-dimethoxy-l,4- 0.2 2.1 5.6 naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 H -60 K562 A549 2-(l-ethoxy-4-methylpentyl)- 5,8-dimethoxy-l,4- 0.01 1.5 3.0 naphthoquinone 2-[ l-(3-methylbutoxy)-4-methyl- pentyl]-5, 8-dimethoxy- 2.5 2.3 3 . 3 1,4-naphthoquinone 2-(l-pentyloxy-4-methylpentyl)- 5,8-dimethoxy-l,4- 2.6 3.0 7.8 naphthoquinone 2-(l-heptyloxy-4-methylpentyl)- 5,8-dimethoxy-l,4- 3.1 6.4 4.7 naphthoquinone 2-(l-dodecyloxy-4-methyl- pentyl)-5, 8-dimethoxy- 6.3 3.7 4.8 1,4-naphthoquinone 2-(l-methoxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 0.05 0.07 1.5 naphthoquinone 2-(l-ethoxy-4-methylpentyl)- 5,8-dihydroxy-l, 4- 0.04 0.08 1.7 naphthoquinone Table 1 (continued) ED 50 (μg/ml) Test Compounds L1210 HL-60 K562 A549 2-[1-(3-methylbutoxy)-4-methyl- pentyl]-5,8-dihydroxy- 0.2 0.09 1.1 1,4-naphthoquinone 2-(l-pentyloxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 0.3 0.2 1.3 naphthoquinone 2-(l-heρtyloxy-4-methy ' lpentyl)- 5,8-dihydroxy-l,4- 0.8 0.2 2.4 naphthoquinone 2-(l-dodecyloxy-4-methyl- pentyl)-5,8-dihydroxy-l,4- >20 >20 >20 naphthoquinone 5-Fluorouracil 0.02 0.2 1.0 3.7 As can be seen from the above result, it is apparant that the novel 5,8-dihydro-l,4-naphthoquinone derivative of formula (IA) of the present invention shows a cytotoxic activity similar to, or superior to, the currently, widely- used anticancer agent, Fluorouracil, and therefore can be used aε a clinically useful anticancer agent. TEST 2 : Animal experiment using sarcoma S-180 cells In this experiment, healthy male ICR mouse weighing 20 to 25g were used as test animal and were fed with water and feed without any restriction in the chamber controlled at the temperature of 23 to 24°C. Aε the feed, the antibiot¬ ic-free feed for mouεe was used. S-180 cells which were incubated for 7 days within abdominal cavity of ICR mouse were separated together with aεcites. To the separated cells waε added sterilized cold physiological saline and the mixture was centrifuged with 400xg for 2 minutes to separate the cell precipitate. The separated cell precipitate was suspended again in steri- lized cold physiological saline and then centrifuged to remove the supernatant. Only S-180 cells were taken, excluding any red bllod cells incorporated therein, washed three timeε with the εame method as above, and then sus¬ pended to obtain the cell suspenεion in concentration of 0 cells/ml by counting the number of cells with a hae a- cyto eter. Each 0.1ml of this cell suspension was trans¬ planted in an abdominal cavity. After 24 hours from the transplantation, mouse were divided so that each group contains 8 to 9 mouεe. The teεt εample was dissolved in a predetermined amount of dimethylsulfoxide to prepare the stock εolution which waε stored at 4°C. 30μl of the εtock εolution waε taken and then mixed with 1.5ml of physiological saline. 0.1ml of this mixture was intraperitoneally injected to the test animal. To the control group, 2% dimethylsulfoxide-physi¬ ological saline solution was injected. Meanwhile, doxoru- bicin which is used as the comparative drug waε dissolved in 2% dimethylsulfoxide-physiological saline solution and then injected in an amount of 0.5mg(titer) /kg. The sched¬ ule for injection comprises a total of 7 to 8 injections in the manner that after the transplantation of cancer cells 0.1ml of the test sample per a day is administered for 2 to 4 days followed by the rest for one day. The survival rate waε calculated on the baεiε of the date on which all of one control group is died (approximately 18 to 20 days) . The survival rate (T/C, %) was calculated by the following equation as proposed in NIC'ε protocol : Average survived period in the test group Survival rate (T/C, %) = X 100 Average survived period in the control group The results as obatined above are described in the following Table 2. Table Anticancer activity of the compound of the present invention against S-180 sarcoma cells Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (% ) 50 days 2-(l-acetyloxy-4-methyl-3- pentenyl)-5,8-dihydroxy- 1.65 (5) 160 0/8 1,4-naphthoquinone 2-(1-monochloroacetyloxy- 4-methyl-3-pentenyl)-5,8- 3.64 (10) 102 0/8 dihydroxy-1,4-naphthoquinone 2-(l-trichloroacetylox ' y-4- methyl-3-pentenyl)-5,8- 4.33 (10) 134 0/8 dihydroxy-1,4-naphthoquinone 2-(l-n-propionyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 1.72 (5) 100 0/8 1,4-naphthoquinone 2-(l-n-butanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 3.58 (10) 181 0/8 1,4-naphthoquinone 2-(l-isobutanoyloxy-4-methyl- 3-pentenyl)-5, 8-dihydroxy- 3.58 (10) 185 1/8 1,4-naphthoquinone 2-(l-n-hexanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 3.86 (10) 214 3/9 1, 4-naphthoquinone Table 2 (continued) Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (%) 50 days 2-[1-(4-pentenoyl)oxy-4-methyl- 3-pentenyl]-5,8-dihydroxy- 3.70 (10) 180 1/7 1,4-naphthoquinone 2-[l-(3,3-dimethyl)acryloxy-4- methyl-3-pentenyl]-5,8- 3.70 (10) 179 2/8 dihydroxy-1,4-naphthoquinone 2-(l-phenylacetyloxy-4 ' -methyl- 3-pentenyl)-5,8-dihydroxy- 4.06 (10) 183 0/8 1,4-naphthoquinone 2-[l-(trans-2-hexenoyl)oxy-4- methyl-3-pentenyl]-5,8- 3.84 (10) 160 1/8 dihydroxy-1,4-naphthoquinone 2-(1-(trans-3-hexenoyl)oxy-4- methyl-3-pentenyl]-5,8- 3.84 (10) 200 2/8 dihydroxy-1,4-naphthoquinone 2-(1-(6-heptenoyl)oxy-4-methyl- 3-pentenyl]-5,8-dihydroxy- 3.98 (10) 192 1/8 1,4-naphthoquinone 2-(l-n-octanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 6.27 (15) 235 2/9 1,4-naphthoquinone Table 2 (continued) Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (%) 50 days 2-(l-n-nonanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 4.28 (10) 206 0/8 1,4-naphthoquinone 2-(l-n-decanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 6.72 (15) 110 0/9 1,4-naphthoquinone 2-(l-lauryloxy-4-methy ' l- 3-pentenyl)-5,8-dihydroxy- 7.14 (15) 110 0/9 1,4-naphthoquinone 2-(l-diphenylacetyloxy-4- methyl-3-pentenyl)-5,8- 7.23 (15) 208 2/8 dihydroxy-1,4-naρhthoquinone 2-(l-undecylenoyloxy-4- methyl-3-pentenyl)-5, 8- 6.81 (15) 110 0/8 dihydroxy-1,4-naphthoquinone 2-(l-stearyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 8.31 (15) 110 0/9 1,4-naρhthoquinone 2-(l-palmityloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 7.89 (15) 109 0/9 1,4-naρhthoquinone Table 2 (continued) Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (%) 50 days 2-(l-oleyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 8.28 (15) 130 0/9 1,4-naphthoquinone 2-(l-linolenyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 8.22 (15) 125 0/9 1,4-naphthoquinone 2-[1-(trans-retinoyl)oxy-4- methyl-3-pentenyl]-5,8- 17.3 (15) 107 0/8 dihydroxy-1,4-naphthoquinone 2-[l-(cis-retinoyl)oxy-4- methyl-3-pentenyl]-5,8- 17.3 (15) 125 0/9 dihydroxy-1,4-naphthoquinone 2-(l-pentanoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 3.72 (10) 165 0/8 1,4-naphthoquinone 2-[l-(trans-2-pentenyloxy)-4- methyl-3-pentenyl]-5,8- 5.61 (15) 210 1/7 dihydroxy-1,4-naphthoquinone 2-[l-(2,4-hexadienoyloxy)-4- methyl-3-pentenyl]-5,8- 3.82 (10) 185 2/8 dihydroxy-1,4-naphthoquinone Table 2 (continued) Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (%) 50 days 2-[ l-(2, 6-heptadienoyloxy)-4- methyl-3-pentenyl ]-5,8- 3.96 (10) 180 1/8 dihydroxy-1,4-naphthoquinone 2-(l-benzoyloxy-4-methyl- 3-pentenyl)-5,8-dihydroxy- 3.92 (10) 135 0/8 1,4-naphthoquinone 2-[1-(9,12-octadecenyl'oxy)- 4-methyl-3-pentenyl]-5, 8- 8.25 (15) 100 0/8 dihydroxy-1,4-naphthoquinone 2-(l-hydroxy-4-methylpentyl)- 5, 8-dimethoxy-l,4- 3.18 (10) 120 0/8 naphthoquinone 2-(l-hydroxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 1.95 (5) 120 0/8 naphthoquinone 2-(1-hydroxytridecyl)-5,8- dihydroxy-1,4-naphthoquinone 3.38 (10) 113 0/8 2-(1-acetoxyhexyl)-5,8- dihydroxy-1, 4-naphthoquinone 1.66 (5) 150 2/8 Table 2 (continued) Dose T/C Number of mouse Test Compounds g/kg/day survived for (μmole) (%) 50 days 2-(1-hexanoyloxyhexyl)-5,8- dihydroxy-1,4-naphthoquinone 3.88 (10) 151 0/7 2-(1-octanoyloxyhexyl)-5,8- dihydroxy-1,4-naphthoquinone 6.24 (15) 95 0/8 2-[1-(trans-3-hexenoyloxy)- hexyl]-5,8-dihydroxy- 3.86 (10) 105 0/7 1,4-naphthoquinone 2-(l-acetoxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 1.66 (5) 188 1/7 naphthoquinone 2-(l-hexanoyloxy-4-methyl- pentyl)-5,8-dihydroxy- 3.88 (10) 151 0/8 1,4-naphthoquinone 2-(l-octanoyloxy-4-methyl- pentyl)-5,8-dihydroxy- 6.24 (15) 131 0/8 1,4-naphthoquinone 2-[l-(trans-3-hexenoyloxy)- 4-methylpentyl]-5,8-dihydroxy- 3.86 (10) 160 0/7 1,4-naphthoquinone Table 1 (continued) Dose T/C Number of mouse Test Compounds mg/kg/day survived for (μmole) (%) 50 days 2-(1-acetoxydecyl)-5,8- dihydroxy-1,4-naphthoquinone 3.88 (10) 197 1/7 2-[1-(trans-3-hexenoyloxy)- decyl]-5,8-dihydroxy- 4.42 (10) 130 0/7 1,4-naphthoquinone 2-(1-acetoxytridecyl)-5,8- dihydroxy-1,4-naphthoq inone 4.30 (10) 131 1/7 2-(l-ethoxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 3.46 (10) 105 0/8 naphthoquinone 2-(l-methoxy-4-methylpentyl)- 5,8-dihydroxy-l,4- 3.04 (10) 126 0/8 naphthoquinone 2-[1-(3-methyIbutoxy)-4-methyl- pentyl]-5,8-dihydroxy- 5.49 (15) 186 0/7 1,4-naphthoquinone Doxorubicin 0.5 (1.2) 230 4/9 Aε can be seen from the above result, it is apparant that the compound of the present invention showε a potent cytotoxic activity against cancer cells and further exhib- itε an excellent LSI effect εimilar to, or superior to, the currently, widely-used anticancer agent, Doxorubicin, in mouεe suffering from S-180 sarcoma, and therefore can be uεed as a clinically useful anticancer agent.

Claims: WHAT IS CLAIMED IS A process for preparing 5, 8-dihydronaphthoquinone derivatives repreεented by the following general formula (I) : in which R 1 repreεentε alkyl or alkenyl, R 2 repreεentε hydrogen, alkyl or a group -C(0)R wherein R repreεentε alkyl, alkenyl, aryl, aral¬ kyl or aralkenyl, which can be εubεtituted or unεubεtituted with one or more halogen(s) , and R- represents hydrogen or alkyl, characterized in that (A) a compound having the following general formula (ID : wherein R , R 2 and R 3 are defined as previously described and R represents alkyl, is oxidized with ceriu (IV) ammonium nitrate in a suitable solvent, or (B) a compound having the following general formula (la) : wherein R 1 and R 2 are defined aε previouεly described and R 3a represents alkyl, is dealkylat- ed to prepare a compound having the following general formula (lb) : wherein R 1 and R?^ are defined as previously described, or (C) a compound having the following general formula (Ic) : wherein R 1 and R J are defined as previously described, is reacted with a compound of formula RCOOH wherein R is defined aε previously de- εcribed/ in the presence of an organic base and dicyclohexylcarbodiimide to prepare a compound having the following general formula (Id) : wherein R 1 , R 3 and R are defined aε previouεly described. The process as defined in claim 1, characterized in that in the method (A) cerium (IV) ammonium nitrate is used in an amount of 1 to 10 mole with respect to 1 mole of the compound of formula (II) . The process as defined in claim 1, characterized in that in the method (A) the solvent is acetonitrile or dimethyIformamide. The procesε aε defined in claim 1, characterized in that in the method (B) a dealkylating agent is boron tribromide, HCl-pyridine, aluminum chloride or silver oxide-nitric acid compound. The process as defined in claim 4, characterized in that εilver oxide-nitric acid compound is used as dealkylating agent. The proceεs as defined in claim 1, characterized in that in the method (C) the reaction solvent is an optionally chlorinated hydrocarbon solvent. The procesε aε defined in claim 1, characterized in that in the method (C) 1.0 to 2.0 mole of dicyclohex¬ ylcarbodiimide and 0.01 to 0.5 mole of the organic baεe are uεed with reεpect to 1 mole of the compound of formula (Ic) . A novel 5,8-dihydronaphthoquinone derivative repre- εented by the following general formula (IA) : in which R J represents alkyl or alkenyl, R 2a represents hydrogen, alkyl or a group -C(0)R wherein R represents alkyl, alkenyl, aryl, aralkyl or aralkenyl, which can be subεtituted or unsubstituted with one or more halogen(s), and R- represents hydrogen or alkyl, provided that when R 2a is hydrogen or a group -C(0)R and R 3 is hydrogen, R 1 is other than 3-methy1-2-butenyl; and when R 2a and R 3 independently of one another represent hydrogen or methyl, R 1 is other than 3-methylbutyl. 9. The 5,8-dihydronaphthoquinone derivative of formula (I) as defined in claim 8, wherein R represents C 1 ~ C 15 alkyl or C 2 -C 15 alkenyl, R 2a repreεentε hydrogen, C 1 -C 15 alkyl or a group -C(0)R wherein R representε c l~ c 15 alkyl, C 2 ~C 15 alkenyl, phenyl, phenyl-C 1 ~C 15 alkyl or phenyl-C 2 -C 15 alkenyl, which can be εubεti¬ tuted or unsubstituted with one or more chlorine atom(ε) , and R represents hydrogen or c ι~ c 5 alkyl, provided that when R 2a is hydrogen or a group -C(0)R and R 3 is hydrogen, R 1 is other than 3-methyl-2-bute- nyl; and when R 2a and R 3 independently of one another represent hydrogen or methyl, R 1 is other than 3- ethylbutyl. 10- An anticancer composition containing the 5,8-dihydro- naphthoquinone derivative of formula (IA) according to claims 8 as an active ingredient.

Inventors: AHN BYUNG ZUN, BAIK KYONG UP, AHN, BYUNG, ZUN, BAIK, KYONG, UP
Applicants: AHN BYUNG ZUN, BAIK KYONG UP, AHN, BYUNG, ZUN, BAIK, KYONG, UP
Application year: 1994
Main classification: C07C69
IPC codes: A61K31, A61P35, C07C43, C07C46, C07C50, C07C67, C07C69